Update docker/build-push-action action to v6.8.0

Author: renovate[bot]

.github/workflows/build.yaml

@@ -19,7 +19,7 @@ jobs:
 
     - name: Build and push Docker image
       id: build-and-push
-      uses: docker/build-push-action@v6.7.0
+      uses: docker/build-push-action@v6.8.0
       with:
         context: .
         platforms: linux/amd64,linux/arm64

.github/workflows/release.yaml

@@ -89,7 +89,7 @@ jobs:
 
     - name: Build and push Docker image
       id: build-and-push
-      uses: docker/build-push-action@v6.7.0
+      uses: docker/build-push-action@v6.8.0
       with:
         context: .
         platforms: linux/amd64,linux/arm64