Merge branch 'ml-note-requires-admin' into 'master'

Note that `:requires_admin` should be added

See merge request gitlab-org/gitlab!29460

doc/development/testing_guide/end_to_end/feature_flags.md

 # Testing with feature flags
 
-To run a specific test with a feature flag enabled you can use the `QA::Runtime::Feature` class to enabled and disable feature flags ([via the API](../../../api/features.md)).
+To run a specific test with a feature flag enabled you can use the `QA::Runtime::Feature` class to enable and disable feature flags ([via the API](../../../api/features.md)).
 
 Note that administrator authorization is required to change feature flags. `QA::Runtime::Feature` will automatically authenticate as an administrator as long as you provide an appropriate access token via `GITLAB_QA_ADMIN_ACCESS_TOKEN` (recommended), or provide `GITLAB_ADMIN_USERNAME` and `GITLAB_ADMIN_PASSWORD`.
 
+Please be sure to include the tag `:requires_admin` so that the test can be skipped in environments where admin access is not available.
+
 ```ruby
-context "with feature flag enabled" do
+context "with feature flag enabled", :requires_admin do
   before do
     Runtime::Feature.enable('feature_flag_name')
   end