Adds a new workflow to cleanup image tags which no longer have an associated branch

.github/workflows/cleanup-tags.yml

@@ -0,0 +1,48 @@
+name: Cleanup Image Tags
+
+on:
+  schedule:
+    - cron: '0 0 * * SAT'
+  delete:
+  pull_request:
+    types:
+      - closed
+  push:
+    paths:
+      - ".github/workflows/cleanup-tags.yml"
+      - ".github/scripts/cleanup-tags.py"
+      - ".github/scripts/common.py"
+
+env:
+  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+jobs:
+  cleanup:
+    name: Cleanup Image Tags
+    runs-on: ubuntu-20.04
+    permissions:
+      packages: write
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v3
+      -
+        name: Login to Github Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      -
+        name: Set up Python
+        uses: actions/setup-python@v3
+        with:
+          python-version: "3.9"
+      -
+        name: Install fastai GitHub API
+        run: |
+          python -m pip install ghapi requests
+      -
+        name: Cleanup feature tags
+        run: |
+          python ${GITHUB_WORKSPACE}/.github/scripts/cleanup-tags.py --loglevel info