Update Dockerfile

Dockerfile

@@ -99,7 +99,7 @@ RUN groupadd --gid ${USER_GID} ${USERNAME} \
     && chown -R ${USERNAME}:${USERNAME} ${OPENVSCODE_SERVER_ROOT} \
     && chown -R ${USERNAME}:${USERNAME} /home/${USERNAME}
 
-USER $USERNAME
+USER root
 
 # 安装 oh-my-zsh
 RUN yes | sh -c "$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"