Update docker/build-push-action action to v6

Author: renovate[bot]

.github/workflows/docker-build.yml

@@ -51,7 +51,7 @@ jobs:
 
       - name: Build and push Docker image
         id: build
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64

.github/workflows/release.yml

@@ -60,7 +60,7 @@ jobs:
 
       - name: Build and push Docker image
         id: build
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64