Initial image build attempt

.gitea/workflows/build.yaml

@@ -0,0 +1,33 @@
+name: Build and push
+
+on:
+  push:
+    branches: [master]
+
+jobs:
+  build:
+    name: Build and push images
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install buildah
+        run: |
+          apt-get -y update
+          apt-get -y install buildah
+
+      - name: Build Ubuntu 22.04
+        id: build
+        uses: redhat-actions/buildah-build@v2
+        with:
+          image: git.nul.ie/dev/actions-ubuntu
+          tags: '22.04'
+          containerfiles: |
+            ubuntu.Containerfile
+      - name: Push Ubuntu 22.04
+        uses: redhat-actions/push-to-registry@v2
+        with:
+          image: ${{ steps.build.outputs.image }}
+          tags: ${{ steps.build.outputs.tags }}
+          registry: git.nul.ie
+          username: dev
+          password: ${{ secrets.PUSH_TOKEN }}