Add gitea ci

.gitea/workflows/build.yml

@@ -0,0 +1,36 @@
+name: Build Docker images
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        version:
+          - "3"
+    steps:
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      -
+        name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      -
+        name: Build and push image
+        uses: docker/build-push-action@v5
+        with:
+          push: true
+          tags: eumau/postfix:${{ matrix.version }}
+          platforms: linux/amd64,linux/arm64