Update docker/setup-buildx-action digest to 6a58db7

Author: renovate[bot]

.github/workflows/docker-publish.yml

@@ -46,7 +46,7 @@ jobs:
 
       # Workaround: https://github.com/docker/build-push-action/issues/461
       - name: Setup Docker buildx
-        uses: docker/setup-buildx-action@8c0edbc76e98fa90f69d9a2c020dcb50019dc325
+        uses: docker/setup-buildx-action@6a58db7e0d21ca03e6c44877909e80e45217eed2
 
       # Login against a Docker registry except on PR
       # https://github.com/docker/login-action