Add group and url to flags

Add group and url to flags
that pburdette has created for
tracking purposes.

config/feature_flags/development/ci_instance_variables_ui.yml

 ---
 name: ci_instance_variables_ui
-introduced_by_url: 
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/33510
 rollout_issue_url:
-group: 
+group: group::continuous integration
 type: development
 default_enabled: true

config/feature_flags/development/new_variables_ui.yml

 ---
 name: new_variables_ui
-introduced_by_url: 
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/25260
 rollout_issue_url:
-group: 
+group: group::continuous integration
 type: development
 default_enabled: true