deploy image when tagging (#792)

Reviewed-on: https://gitea.com/gitea/tea/pulls/792
Reviewed-by: techknowlogick <techknowlogick@noreply.gitea.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-committed-by: Lunny Xiao <xiaolunwen@gmail.com>

.gitea/workflows/release-tag.yml

@@ -39,3 +39,43 @@ jobs:
           GPGSIGN_PASSPHRASE: ${{ secrets.GPGSIGN_PASSPHRASE }}
           GPG_FINGERPRINT: ${{ steps.import_gpg.outputs.fingerprint }}
           GITEA_TOKEN: ${{ secrets.RELEASE_TOKEN }}
+  release-image:
+    runs-on: ubuntu-latest
+    env:
+      DOCKER_ORG: gitea
+      DOCKER_LATEST: nightly
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # all history for all branches and tags
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker BuildX
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Get tag version without v
+        id: get_version
+        run: echo "VERSION=${GITHUB_REF#refs/tags/v}" >> $GITHUB_ENV
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        env:
+          ACTIONS_RUNTIME_TOKEN: '' # See https://gitea.com/gitea/act_runner/issues/119
+        with:
+          context: .
+          file: ./Dockerfile
+          platforms: |
+            linux/amd64
+            linux/arm64
+          push: true
+          tags: |
+            gitea/tea:${{ env.VERSION }}