Enable the FF ci_include_rules by default

It's already enabled on GitLabcom

Changelog: added
MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/67409

config/feature_flags/development/ci_include_rules.yml

@@ -5,4 +5,4 @@ rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/337507
 milestone: '14.2'
 type: development
 group: group::pipeline authoring
-default_enabled: false
+default_enabled: true

doc/ci/yaml/index.md

@@ -450,12 +450,12 @@ that proposes expanding this feature to support more variables.
 
 #### `rules` with `include`
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/276515) in GitLab 14.2.
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/276515) in GitLab 14.2.
+> - [Enabled on GitLab.com](https://gitlab.com/gitlab-org/gitlab/-/issues/337507) in GitLab 14.3 and is ready for production use.
+> - [Enabled with `ci_include_rules` flag](https://gitlab.com/gitlab-org/gitlab/-/issues/337507) for self-managed GitLab in GitLab 14.3 and is ready for production use.
 
-NOTE:
-On self-managed GitLab, by default this feature is not available. To make it available,
-ask an administrator to [enable the `ci_include_rules` flag](../../administration/feature_flags.md).
-On GitLab.com, this feature is not available. The feature is not ready for production use.
+FLAG:
+On self-managed GitLab, by default this feature is available. To hide the feature per project or for your entire instance, ask an administrator to [disable the `ci_include_rules` flag](../../administration/feature_flags.md). On GitLab.com, this feature is available.
 
 You can use [`rules`](#rules) with `include` to conditionally include other configuration files.
 You can only use `rules:if` in `include` with [certain variables](#variables-with-include).