Update comment about repository.DISABLED_REPO_UNITS in app.example.ini (#21343)

Add allowed values: `repo.projects`

custom/conf/app.example.ini

@@ -887,7 +887,7 @@ ROUTER = console
 ;USE_COMPAT_SSH_URI = false
 ;;
 ;; Close issues as long as a commit on any branch marks it as fixed
-;; Comma separated list of globally disabled repo units. Allowed values: repo.issues, repo.ext_issues, repo.pulls, repo.wiki, repo.ext_wiki
+;; Comma separated list of globally disabled repo units. Allowed values: repo.issues, repo.ext_issues, repo.pulls, repo.wiki, repo.ext_wiki, repo.projects
 ;DISABLED_REPO_UNITS =
 ;;
 ;; Comma separated list of default repo units. Allowed values: repo.code, repo.releases, repo.issues, repo.pulls, repo.wiki, repo.projects.