update warn message

lib/crowi/dev.js

@@ -48,7 +48,7 @@ class CrowiDev {
       orgCreateConnection.call(this, socket);
 
       socket.on('error', (err) => {
-        console.warn(`[WARN] Worthless error in client socket: '${err}'`);
+        console.warn(`[WARN] An insignificant error occured in client socket: '${err}'`);
       });
     }
   }