chore(deps): update docker/build-push-action digest to 9f6f8c9 (#91)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/docker.yaml

@@ -50,7 +50,7 @@ jobs:
             type=semver,pattern={{major}}.{{minor}}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@4a13e500e55cf31b7a5d59a38ab2040ab0f42f56
+        uses: docker/build-push-action@9f6f8c940b91232557f8699b21341a08624a8dce
         with:
           context: .
           push: ${{ github.event_name != 'pull_request' }}