Add a local registry in github actions for us to test with

.github/workflows/test.yml

@@ -40,6 +40,7 @@ env:
   GIT_AUTHOR_EMAIL: ci-user@github.local
   GIT_AUTHOR_NAME: CI User
 
+
 jobs:
   test:
     # Don't run scheduled tests on forks
@@ -72,8 +73,22 @@ jobs:
             python_version: "3.9"
             repo_type: venv
 
+    services:
+      # So that we can test this in PRs/branches
+      local-registry:
+        image: registry:2
+        ports:
+          - 5000:5000
+
     steps:
       - uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+        with:
+          # Allows pushing to registry on localhost:5000
+          driver-opts: network=host
+
       - uses: actions/setup-python@v5
         with:
           python-version: "${{ matrix.python_version }}"