use multiple runners for the multi-arch build

.gitea/workflows/ci.yml

@@ -76,26 +76,21 @@ jobs:
     needs: tests
     steps:
       - uses: actions/checkout@v4
+      - name: Prepare
+        run: |
+          platform=${{ matrix.arch.platform }}
+          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV
+      - name: Generate metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
       - name: Login to the Container Registry
         uses: docker/login-action@v3
         with:
           registry: brosner.dev
           username: brosner
           password: ${{ secrets.CI_TOKEN }}
-      - name: Generate metadata
-        id: meta
-        uses: docker/metadata-action@v5
-        with:
-          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
-          tags: |
-            type=ref,event=branch
-            type=ref,event=pr
-            type=sha
-          labels: |
-            org.opencontainers.image.title=teufa
-            org.opencontainers.image.description=teufa container image
-            org.opencontainers.image.source=https://brosner.dev/brosner/teufa
-            org.opencontainers.image.licenses=MIT
       - name: Setup docker buildx
         uses: docker/setup-buildx-action@v3
       - name: Build image