Add workflow for tagging quality mod issues

.github/workflows/tag-quality-mod-issues.yml

@@ -0,0 +1,18 @@
+name: Tag Quality mod team
+
+on:
+  issues:
+    types: [labeled]
+
+jobs:
+  tag:
+    if: github.event.label.name == 'quality-guidelines'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Add comment tagging the team
+        uses: peter-evans/create-or-update-comment@v4
+        with:
+          token: ${{ secrets.FLATHUBBOT_TOKEN }}
+          issue-number: ${{ github.event.issue.number }}
+          body: |
+            Thank you for opening this issue! cc @flathub/quality-moderation