Update docker/metadata-action digest to 6c3ca5d

Author: renovate[bot]

Diff for: .github/workflows/docker-publish.yml

@@ -64,7 +64,7 @@ jobs:
       # https://github.com/docker/metadata-action
       - name: Extract Docker metadata
         id: meta
-        uses: docker/metadata-action@507c2f2dc502c992ad446e3d7a5dfbe311567a96
+        uses: docker/metadata-action@6c3ca5dfa6895029f82e5b2f26f060bc0d3c6a2c
         with:
           images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}