Actions: Add publish job

.forgejo/workflows/publish.yaml

@@ -31,3 +31,19 @@ jobs:
       - name: load image into podman
         run: |
           podman load < ${{ steps.pkgs.outputs.pkgs-name }}
+
+  publish:
+    runs-on: nixos-latest
+    strategy: *strategy
+    steps:
+      - name: login to container registry
+        uses: https://code.forgejo.org/docker/login-action@v2
+        with:
+          registry: git.flyinggecko.org
+          username: flyinggecko
+          password: ${{ secrets.REGISTRY_TOKEN }}
+      - name: publish image
+        env:
+          IMAGE: git.flyinggecko.org/flyinggecko/oci-images/${{ matrix.container }}:${{ matrix.version }}
+        run: |
+          docker push "${IMAGE}"