feat: cleanup old GitHub packages

This commit refactors the code to include a new step called "package-cleanup" in the docker-publish workflow. The step is responsible for deleting old package versions of the "linuxgsm" container, keeping only one version and deleting untagged versions. This change improves the efficiency and organization of our GitHub packages.

.github/workflows/docker-publish.yml

@@ -134,3 +134,16 @@ jobs:
           tags: |
             gameservermanagers/linuxgsm:ubuntu-18.04
             ghcr.io/gameservermanagers/linuxgsm:ubuntu-18.04
+
+  package-cleanup:
+    name: Cleanup Old GitHub Packages
+    needs: [ build-ubuntu-1804, build-ubuntu-2004, build-ubuntu-2204 ]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Delete Package Versions
+        uses: actions/delete-package-versions@v4
+        with:
+          package-name: linuxgsm
+          package-type: container
+          min-versions-to-keep: 1
+          delete-only-untagged-versions: true