Recommend True and False for boolean attributes.

RELNOTES: None.
PiperOrigin-RevId: 186501019
diff --git a/site/docs/skylark/bzl-style.md b/site/docs/skylark/bzl-style.md
index edb8433..bf8a372 100644
--- a/site/docs/skylark/bzl-style.md
+++ b/site/docs/skylark/bzl-style.md
@@ -72,9 +72,13 @@
   native.cc_library(
     name = name,
     srcs = filtered_srcs,
+    testonly = True,
   )
 ```
 
+* Prefer values `True` and `False` instead of `0` and `1` for boolean values
+  (e.g. when using a boolean attribute in a rule).
+
 * Do not use the `print()` function in production code; it is only intended for
   debugging, and will spam all direct and indirect users of your `.bzl` file.
   The only exception is that you may submit code that uses `print()` if it is