Update docker/metadata-action digest to 906ecf0 (#354)

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

Author: renovate[bot]

.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@b53be03109c4ef6f6cc7aa545b84b17a7fe51c1e
+        uses: docker/metadata-action@906ecf0fc0a80f9110f79d9e6c04b1080f4a2621
         with:
           images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}