Push docker images also to ghcr.io

.github/workflows/docker.yml

@@ -30,7 +30,7 @@ jobs:
         id: meta
         uses: docker/metadata-action@v3
         with:
-          images: 42wim/matterbridge
+          images: 42wim/matterbridge,ghcr.io/42wim/matterbridge
           flavor: |
             latest=true
           tags: |
@@ -47,7 +47,7 @@ jobs:
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
-      - 
+      -
         name: Log into registry ghcr.io
         uses: docker/login-action@v1
         if: github.event_name != 'pull_request'