Migrate all absolute links (/versions/master/...) in site/docs to use relative links to be compatible with versioned docs

For files in..

* `site/docs`: `s;https://docs.bazel.build/versions/master/;;g`
* `site/docs/skylark`, `site/docs/tutorial`: `s;https://docs.bazel.build/versions/master/;../;g`

Closes #6935.

Change-Id: I177c0c1d780dd6d4bc8f40c58506fc3251abe1e3
PiperOrigin-RevId: 225622408

site/docs/remote-execution.md

diff --git a/site/docs/remote-execution.md b/site/docs/remote-execution.md
index 3a5751e..66a9cb6 100644
--- a/site/docs/remote-execution.md
+++ b/site/docs/remote-execution.md
@@ -46,4 +46,4 @@
 
 Remote execution of Bazel builds imposes a set of mandatory configuration
 constraints on the build. For more information, see
-[Adapting Bazel Rules for Remote Execution](https://docs.bazel.build/versions/master/remote-execution-rules.html).
+[Adapting Bazel Rules for Remote Execution](remote-execution-rules.html).