chore(deps): update ghcr.io/nodebb/nodebb docker tag to v4.2.1 (#3660)

* chore(deps): update ghcr.io/nodebb/nodebb docker tag to v4.2.1

* Update app version [skip ci]

---------

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: github-action update-app-version <githubaction@githubaction.com>

nodebb/4.2.1/docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   nodebb:
-    image: ghcr.io/nodebb/nodebb:4.2.0
+    image: ghcr.io/nodebb/nodebb:4.2.1
     container_name: ${CONTAINER_NAME}
     restart: unless-stopped
     networks: