[ Fixing Permission Error ] (#1842)

- Inside container, we can't change /etc files without root permissions

ide-theia/Dockerfile

@@ -2,4 +2,6 @@ FROM theiaide/theia
 
 LABEL maintainer="ahkui <ahkui@outlook.com>"
 
-RUN echo 'fs.inotify.max_user_watches=524288' >> /etc/sysctl.conf
+USER root
+
+RUN echo 'fs.inotify.max_user_watches=524288' >> /etc/sysctl.conf