Bump docker/build-push-action from 5 to 6

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 5 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v5...v6)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/aws-ecs-deploy-backend.yml

@@ -76,7 +76,7 @@ jobs:
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v3
     - name: Build and push
-      uses: docker/build-push-action@v5
+      uses: docker/build-push-action@v6
       with:
         context: ${{ env.DOCKER_PATH }}
         file: ${{ env.DOCKERFILE }}

.github/workflows/aws-ecs-deploy-frontend.yml

@@ -80,7 +80,7 @@ jobs:
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v3
     - name: Build and push
-      uses: docker/build-push-action@v5
+      uses: docker/build-push-action@v6
       with:
         context: ${{ env.DOCKER_PATH }}
         file: ${{ env.DOCKERFILE }}