Add build and push action

.forgejo/workflows/docker.yaml

@@ -0,0 +1,28 @@
+on: 
+  push:
+    branches:
+      - main
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Login to Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.GITHUB_SERVER_URL }}
+          username: ${{ env.GITHUB_REPOSITORY_OWNER	 }}
+          password: ${{ env.GITHUB_TOKEN }}
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      -
+        name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          push: true
+          tags: ${{ env.GITHUB_REPOSITORY }}:latest