Update docker/metadata-action action to v5.6.1

| datasource  | package                | from   | to     |
| ----------- | ---------------------- | ------ | ------ |
| github-tags | docker/metadata-action | v5.5.1 | v5.6.1 |


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

Author: renovate[bot]

.github/workflows/ci.yml

@@ -114,7 +114,7 @@ jobs:
 
       - name: Docker meta
         id: meta
-        uses: docker/metadata-action@8e5442c4ef9f78752691e2d8f8d19755c6f78e81 # v5.5.1
+        uses: docker/metadata-action@369eb591f429131d6889c46b94e711f089e6ca96 # v5.6.1
         with:
           images: |
             name=nginx/nginx-prometheus-exporter,enable=${{ github.event_name != 'pull_request' }}