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

Author: renovate[bot]

.github/workflows/release.yml

@@ -65,7 +65,7 @@ jobs:
           echo "pgvecto=${PGVECTO_FROM_TAG}" >> "$GITHUB_OUTPUT"
 
       - name: Build and Push Image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64

.github/workflows/verify.yml

@@ -64,7 +64,7 @@ jobs:
           echo "pgvecto=${PGVECTO_FROM_TAG}" >> "$GITHUB_OUTPUT"
 
       - name: Build Image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64