Add scheduled image build, prune image one hour later

.github/workflows/cron_build.yml

@@ -0,0 +1,38 @@
+---
+name: Weekly image build
+on:
+  schedule:
+    - cron: '22 0 * * 1' # 22 past midnight on Monday
+
+jobs:
+  build_and_deploy:
+      runs-on: ubuntu-latest
+      strategy:
+        fail-fast: false
+        matrix:
+          images:
+            - ubuntu/focal
+            - ubuntu/jammy
+            - ubuntu/focal_desktop
+      steps:
+        - name: Checkout
+          uses: actions/checkout@v4
+          with:
+            submodules: recursive
+        - name: Update submodules to latest version
+          run: git submodule update --recursive --remote
+        - name: Login to GitHub Container Registry
+          uses: docker/login-action@v3
+          with:
+            registry: ghcr.io
+            username: ${{ github.actor }}
+            password: ${{ secrets.GITHUB_TOKEN }}
+        - name: Build image
+          id: build-image
+          run: IMG=${{ matrix.images }} ./pack.sh docker
+        - name: Get image name and tag # grep in the image directory's variables file to find the image name/tag to push to
+          id: get-image-name
+          run: |
+            echo "docker_repo=`grep docker_repo ${{ matrix.images }}/variables.auto.pkrvars.hcl | awk '{print $3}'`"  >> "$GITHUB_OUTPUT"
+        - name: Push image
+          run: docker push ${{ steps.get-image-name.outputs.docker_repo }}

.github/workflows/prune.yml

@@ -2,7 +2,7 @@
 name: Prune Untagged Images
 on:
   schedule:
-    - cron: '22 0 * * *' # 22 past midnight daily
+    - cron: '22 1 * * *' # 22 past 1am daily
   workflow_dispatch:
 
 jobs: