Bump snok/container-retention-policy from 2.1.3 to 2.2.1

Bumps [snok/container-retention-policy](https://github.com/snok/container-retention-policy) from 2.1.3 to 2.2.1.
- [Release notes](https://github.com/snok/container-retention-policy/releases)
- [Commits](snok/container-retention-policy@v2.1.3...v2.2.1)

---
updated-dependencies:
- dependency-name: snok/container-retention-policy
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/ghcr-actions.yml

@@ -17,7 +17,7 @@ jobs:
       packages: write
     steps:
       - name: Delete 'PR' containers older than a week
-        uses: snok/container-retention-policy@v2.1.3
+        uses: snok/container-retention-policy@v2.2.1
         with:
           image-names: sda-doa
           filter-tags: PR*, sha-*
@@ -28,7 +28,7 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Delete all containers older than treee months, using a wildcard
-        uses: snok/container-retention-policy@v2.1.3
+        uses: snok/container-retention-policy@v2.2.1
         with:
           image-names: sda-doa
           filter-tags: v*