Merge branch 'docs-package-tier' into 'master'

Add product tier badges to Package product docs

See merge request gitlab-org/gitlab!57845

doc/administration/packages/container_registry.md

@@ -4,7 +4,7 @@ group: Package
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
 ---
 
-# GitLab Container Registry administration
+# GitLab Container Registry administration **(FREE SELF)**
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/4040) in GitLab 8.8.
 > - Container Registry manifest `v1` support was added in GitLab 8.9 to support

doc/administration/packages/dependency_proxy.md

@@ -4,7 +4,7 @@ group: Package
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
 ---
 
-# GitLab Dependency Proxy administration
+# GitLab Dependency Proxy administration **(FREE SELF)**
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/7934) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.11.
 > - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/273655) to [GitLab Free](https://about.gitlab.com/pricing/) in GitLab 13.6.

doc/administration/packages/index.md

@@ -4,7 +4,7 @@ group: Package
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
 ---
 
-# GitLab Package Registry administration
+# GitLab Package Registry administration **(FREE SELF)**
 
 GitLab Packages allows organizations to use GitLab as a private repository
 for a variety of common package managers. Users are able to build and publish