[misc] re-level log: properly silence unauthorized updateClientPosition

services/real-time/app/js/WebsocketController.js

@@ -356,7 +356,7 @@ module.exports = WebsocketController = {
       cursorData.doc_id,
       function (error) {
         if (error) {
-          logger.warn(
+          logger.info(
             { err: error, client_id: client.id, project_id, user_id },
             "silently ignoring unauthorized updateClientPosition. Client likely hasn't called joinProject yet."
           )