Rules are no longer experimental.

Exact API will continue to evolve, some specific functions
are experimental, but we can't really say that the concept
of rule is experimental.

RELNOTES: None.
PiperOrigin-RevId: 205383939

site/docs/skylark/rules.md

diff --git a/site/docs/skylark/rules.md b/site/docs/skylark/rules.md
index 85a1941..ad550cd 100644
--- a/site/docs/skylark/rules.md
+++ b/site/docs/skylark/rules.md
@@ -5,9 +5,6 @@
 
 # Rules
 
-**Status: Experimental**. We may make breaking changes to the API, but we will
-  announce them.
-
 A rule defines a series of [actions](#actions) that Bazel should perform on
 inputs to get a set of outputs. For example, a C++ binary rule might take a set
 of `.cpp` files (the inputs), run `g++` on them (the action), and return an