add clean action

to remove untagged images from Github package registry

.github/workflows/artifacts.yml

@@ -130,3 +130,20 @@ jobs:
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
+
+  clean:
+    name: remove untagged images from Github package registry
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+    needs: docker
+    steps:
+      - name: ghcr.io cleanup action
+        uses: dataaxiom/ghcr-cleanup-action@v1
+        with:
+          package: mermeid
+          delete-untagged: true
+          dry-run: false
+          validate: true
+          older-than: 2 weeks
+          token: ${{ secrets.GITHUB_TOKEN }}