Add reference to bazel-skylib Gazelle plugin
Also removes reference to abandoned `rules_sass` plugin.
diff --git a/extend.rst b/extend.rst
index 197089a..f9df6b9 100644
--- a/extend.rst
+++ b/extend.rst
@@ -13,8 +13,7 @@
.. _proto.GetProtoConfig: https://godoc.org/github.com/bazelbuild/bazel-gazelle/language/proto#GetProtoConfig
.. _proto.Package: https://godoc.org/github.com/bazelbuild/bazel-gazelle/language/proto#Package
.. _rules_r: https://github.com/grailbio/rules_r
-.. _rules_sass: https://github.com/bazelbuild/rules_sass
-.. _#75: https://github.com/bazelbuild/rules_sass/pull/75
+.. _bazel-skylib: https://github.com/bazelbuild/bazel-skylib/tree/main/gazelle/bzl
.. _bazel_rules_nodejs_contrib: https://github.com/ecosia/bazel_rules_nodejs_contrib#build-file-generation
.. _#803: https://github.com/bazelbuild/bazel-gazelle/issues/803
@@ -47,8 +46,7 @@
Some extensions have been published by the community.
-* `rules_sass`_ has an extension for generating ``sass_library`` and
- ``sass_binary`` rules (currently pending in PR `#75`_).
+* `bazel-skylib`_ has an extension for generating ``bzl_library``.
* `rules_r`_ has an extension for generating rules for R package builds and
tests.
* Ecosia's `bazel_rules_nodejs_contrib`_ has an extension for generating
