Rename bazel_skylib default branch to main.

See https://github.com/bazelbuild/bazel-skylib/branches and
https://github.com/bazelbuild/bazel-skylib/issues/281.

RELNOTES: None.
PiperOrigin-RevId: 368882757
diff --git a/site/docs/configurable-attributes.md b/site/docs/configurable-attributes.md
index 07b5fb2..18091ed 100644
--- a/site/docs/configurable-attributes.md
+++ b/site/docs/configurable-attributes.md
@@ -455,9 +455,9 @@
 ### <a name="selects-with-or"></a>`selects.with_or`
 
 The
-[with_or](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md#selectswith_or)
+[with_or](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md#selectswith_or)
 macro in [Skylib](https://github.com/bazelbuild/bazel-skylib)'s
-[`selects`](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md)
+[`selects`](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md)
 module supports `OR`ing conditions directly inside a `select`:
 
 ```python
@@ -479,9 +479,9 @@
 
 
 The
-[config_setting_group](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md#selectsconfig_setting_group)
+[config_setting_group](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md#selectsconfig_setting_group)
 macro in [Skylib](https://github.com/bazelbuild/bazel-skylib)'s
-[`selects`](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md)
+[`selects`](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md)
 module supports `OR`ing multiple `config_setting`s:
 
 ```python
@@ -522,7 +522,7 @@
 
 If you need a `select` branch to match when multiple conditions match, use the
 [Skylib](https://github.com/bazelbuild/bazel-skylib) macro
-[config_setting_group](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md#selectsconfig_setting_group):
+[config_setting_group](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md#selectsconfig_setting_group):
 
 ```python
 config_setting(
diff --git a/site/docs/platforms.md b/site/docs/platforms.md
index 68d7d46..1e3199e 100644
--- a/site/docs/platforms.md
+++ b/site/docs/platforms.md
@@ -210,7 +210,7 @@
 
 To make your constraints more readable, use
 [skylib](https://github.com/bazelbuild/bazel-skylib)'s
-[`selects.with_or()`](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/selects_doc.md#selectswith_or).
+[`selects.with_or()`](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/selects_doc.md#selectswith_or).
 
 You can express inverse compatibility in a similar way. The following example
 describes a library that is compatible with everything _except_ for ARM.
diff --git a/site/docs/skylark/config.md b/site/docs/skylark/config.md
index 0958c6e..44e0f22 100644
--- a/site/docs/skylark/config.md
+++ b/site/docs/skylark/config.md
@@ -198,7 +198,7 @@
 ```
 
 For a complete list, see
-[Common build setting rules](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/common_settings.bzl).
+[Common build setting rules](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/common_settings.bzl).
 
 ### Using build settings
 
diff --git a/site/docs/skylark/windows_tips.md b/site/docs/skylark/windows_tips.md
index b8b2601..1f960ce 100644
--- a/site/docs/skylark/windows_tips.md
+++ b/site/docs/skylark/windows_tips.md
@@ -172,38 +172,38 @@
   Build rule examples:
 
   - `copy_file()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/copy_file.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/copy_file_doc.md)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/copy_file.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/copy_file_doc.md)):
     copies a file somewhere else, optionally making it executable
 
   - `write_file()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/write_file.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/write_file_doc.md)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/write_file.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/write_file_doc.md)):
     writes a text file, with the desired line endings (`auto`, `unix`, or `windows`), optionally
     making it executable (if it's a script)
 
   - `run_binary()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/run_binary.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/run_binary_doc.md)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/run_binary.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/run_binary_doc.md)):
     runs a binary (or `*_binary` rule) with given inputs and expected outputs as a build action
     (this is a build rule wrapper for `ctx.actions.run`)
 
   - `native_binary()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/native_binary.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/native_binary_doc.md#native_binary)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/native_binary.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/native_binary_doc.md#native_binary)):
     wraps a native binary in a `*_binary` rule, which you can `bazel run` or use in `run_binary()`'s
     `tool` attribute or `native.genrule()`'s `tools` attribute
 
   Test rule examples:
 
   - `diff_test()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/diff_test.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/diff_test_doc.md)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/diff_test.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/diff_test_doc.md)):
     test that compares contents of two files
 
   - `native_test()`
-    ([source](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/native_binary.bzl),
-    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/master/docs/native_binary_doc.md#native_test)):
+    ([source](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/native_binary.bzl),
+    [documentation](https://github.com/bazelbuild/bazel-skylib/blob/main/docs/native_binary_doc.md#native_test)):
     wraps a native binary in a `*_test` rule, which you can `bazel test`
 
 - **On Windows, consider using `.bat` scripts for trivial things.**
diff --git a/site/docs/windows.md b/site/docs/windows.md
index f76a1de..e243bf9 100644
--- a/site/docs/windows.md
+++ b/site/docs/windows.md
@@ -80,11 +80,11 @@
 - Starlark rule that uses `ctx.actions.run_shell()` or `ctx.resolve_command()`
 
 However, `genrule` is often used for simple tasks like
-[copying a file](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/copy_file.bzl)
-or [writing a text file](https://github.com/bazelbuild/bazel-skylib/blob/master/rules/write_file.bzl).
+[copying a file](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/copy_file.bzl)
+or [writing a text file](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/write_file.bzl).
 Instead of using `genrule` (and depending on Bash) you may find a suitable rule
 in the
-[bazel-skylib repository](https://github.com/bazelbuild/bazel-skylib/tree/master/rules).
+[bazel-skylib repository](https://github.com/bazelbuild/bazel-skylib/tree/main/rules).
 When built on Windows, **these rules do not require Bash**.
 
 <a name="bazel-test-without-bash"></a>