ci: Run mirror-images less often

Run it once a night for regular cleanup etc and after each release-image
workflow instead of doing it blindly every 2 hours.

This will only run the mirror job if BOTH build types were
successful, but it is better than nothing, and we have the nightly run
to pick up everything else.

Thanks @jade for the quick feedback and hand-holding in creating this.

.forgejo/workflows/mirror-images.yml

@@ -2,8 +2,11 @@ name: Mirror Container Images
 
 on:
   schedule:
-    # Run every 2 hours
-    - cron: "0 */2 * * *"
+    # Run nightly
+    - cron: "25 2 * * *"
+
+  workflow_call:
+
   workflow_dispatch:
     inputs:
       dry_run:

.forgejo/workflows/release-image.yml

@@ -195,3 +195,10 @@ jobs:
           images: ${{ env.IMAGE_PATH }}
           registry_user: ${{ vars.BUILTIN_REGISTRY_USER || github.actor }}
           registry_password: ${{ secrets.BUILTIN_REGISTRY_PASSWORD || secrets.GITHUB_TOKEN }}
+
+  mirror_images:
+    needs:
+      - merge-maxperf
+      - merge-release
+    runs-on: ubuntu-latest
+    uses: ./.forgejo/workflows/mirror-images.yml