add package cleanup workflow

Author: jamesmoore

.github/workflows/docker-cleanup.yml

@@ -0,0 +1,18 @@
+name: Docker cleanup
+
+on:
+  workflow_dispatch:
+
+permissions:
+  packages: write
+
+jobs:
+  delete_versions:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/delete-package-versions@v5
+      with: 
+        package-name: 'mp3info'
+        package-type: 'container'
+        min-versions-to-keep: 10
+        delete-only-untagged-versions: false