ci: only post release issue notifications on prod deploys

Ref: agrc/release-issue-notifications-action#34

Author: stdavis

Diff for: .github/workflows/release.yml

@@ -67,6 +67,7 @@ jobs:
   notify:
     name: Notifications
     runs-on: ubuntu-latest
+    needs: deploy-prod
     permissions:
       contents: read
       pull-requests: write