do not call app.js directly

https://github.com/NodeBB/NodeBB/issues/6168

start.sh

@@ -88,7 +88,7 @@ ${mongo_cli} --eval "db.objects.update({ _key: \"plugins:active\" }, { \$set: {
 # app    - this is what "nodebb build" calls
 
 echo "=> Updating nodebb (and building assets)"
-/usr/local/bin/gosu cloudron:cloudron node /app/code/app --upgrade --series
+/usr/local/bin/gosu cloudron:cloudron node /app/code/nodebb upgrade --schema --build
 
 echo "=> Starting nodebb"
 exec /usr/local/bin/gosu cloudron:cloudron node /app/code/loader.js --no-daemon --no-silent --series