Merge branch '390954-enable-restrict_special_characters_in_namespace_path' into 'master'

Enable restrict_special_characters_in_namespace_path feature flag

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/127121



Merged-by: Dmitry Gruzd <dgruzd@gitlab.com>
Approved-by: Aman Luthra <aluthra@gitlab.com>
Approved-by: Dmitry Gruzd <dgruzd@gitlab.com>
Co-authored-by: Abdul Wadood <awadood@gitlab.com>

config/feature_flags/development/restrict_special_characters_in_namespace_path.yml

@@ -5,4 +5,4 @@ rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/390954
 milestone: '15.9'
 type: development
 group: group::tenant scale
-default_enabled: false
+default_enabled: true