chore(deps): update docker/build-push-action action to v6

Author: mend-for-github-com[bot]

.github/workflows/build-image.yml

@@ -113,7 +113,7 @@ jobs:
           make build
           
       - name: Build image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: test-app
           push: false