Added workflow

.gitea/workflows/docker-tag-build.yml

@@ -0,0 +1,41 @@
+name: Build and push Docker image on push
+
+on:
+  push:
+    branches:
+      - '**'
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set variables
+        shell: bash
+        run: |
+          echo "IMAGE_NAME=gitea.lostak.dev/lostakj/postfix" >> "$GITHUB_ENV"
+
+      - name: Login to Gitea registry
+        shell: bash
+        run: |
+          echo "${{ secrets.REGISTRY_TOKEN }}" | docker login gitea.lostak.dev -u "${{ secrets.REGISTRY_USER }}" --password-stdin
+
+      - name: Create buildx builder
+        shell: bash
+        run: |
+          docker buildx create --name ci-builder --use || docker buildx use ci-builder
+          docker buildx inspect --bootstrap
+
+      - name: Build and push image
+        shell: bash
+        run: |
+          docker buildx build \
+            --platform linux/amd64 \
+            -t "${IMAGE_NAME}:latest" \
+            --push \
+            .