feat: add automation for ubuntu/* branches asserting quilt patches apply

.github/workflows/packaging-tests.yml

@@ -0,0 +1,37 @@
+name: Integration Tests
+
+on:
+  pull_request:
+    branches:
+      - 'ubuntu/**'
+
+concurrency:
+  group: 'ci-${{ github.workflow }}-${{ github.ref }}'
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: sh -ex {0}
+
+env:
+  RELEASE: focal
+
+jobs:
+  quilt-patch-apply:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: "Checkout"
+        uses: actions/checkout@v3
+        with:
+          # Fetch all tags for tools/read-version
+          fetch-depth: 0
+      - name: Prepare dependencies
+        run: |
+          sudo DEBIAN_FRONTEND=noninteractive apt-get update
+          sudo DEBIAN_FRONTEND=noninteractive apt-get -y install tox quilt
+      - name: Quilt apply and test
+        run: |
+          echo ====== Ensure quilt patches apply to local branch =======
+          quilt push -a
+          tox -e py3
+          quilt pop -a