Bug 1608421 - Only run the bugzilla-components task on mozilla-central. r=jmaher a=pascalc

Differential Revision: https://phabricator.services.mozilla.com/D74329

taskcluster/ci/source-test/file-metadata.yml

@@ -29,6 +29,7 @@ bugzilla-components:
         mach: file-info bugzilla-automation /builds/worker/artifacts
     worker:
         max-run-time: 2700
+    run-on-projects: ['mozilla-central']
     when:
         files-changed:
             - "**"