Update Dockerfile

Dockerfile

@@ -61,7 +61,7 @@ RUN --mount=type=secret,id=GH_TOKEN,mode=0444,required=true \
     git config --global user.email $(cat /run/secrets/GH_EMAIL) && \
     git clone https://$(cat /run/secrets/GH_TOKEN)@github.com/$(cat /run/secrets/GH_USERNAME)/$(cat /run/secrets/REPO_NAME).git /home/coder/cpp_competition
 
-RUN echo "#!/bin/bash \n \ /usr/sbin/cron & exec code-server /home/coder/cpp_competition" > /home/coder/start.sh
+RUN echo "#!/bin/bash \n \cron & exec code-server /home/coder/cpp_competition" > /home/coder/start.sh
 RUN chmod +x /home/coder/start.sh
 
 # 暴露端口