Bump docker/build-push-action from 6 to 7 (#21)

Author: dependabot[bot]

.github/workflows/container.yml

@@ -54,7 +54,7 @@ jobs:
             type=semver,pattern={{major}}.{{minor}}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           push: true