Merge branch 'docs-offline-quickstart-metadata' into 'master'

Add metadata to offline guides

See merge request gitlab-org/gitlab!49696

doc/topics/offline/index.md

 ---
-stage: none
-group: unassigned
+stage: Enablement
+group: Distribution
 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
 ---
 

doc/topics/offline/quick_start_guide.md

 ---
-stage: none
-group: unassigned
+stage: Enablement
+group: Distribution
 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
 ---