build: fix docker build by ensuring qemu (#10492)

Signed-off-by: Jakob Borg <jakob@kastelo.net>

.github/workflows/build-infra-dockers.yaml

@@ -59,6 +59,9 @@ jobs:
             mv ${{ matrix.pkg }} ${{ matrix.pkg }}-linux-"$arch"
           done
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 

.github/workflows/build-syncthing.yaml

@@ -1045,6 +1045,9 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
@@ -1072,7 +1075,7 @@ jobs:
           echo "DOCKER_TAGS=$tags" >> $GITHUB_ENV
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           file: ${{ matrix.dockerfile }}