Update Dockerfile

Dockerfile

@@ -32,6 +32,7 @@ COPY config.yaml /home/coder/.config/code-server/
 COPY create_languagepacks.sh /home/
 COPY cph-ng-0.5.5.vsix /home/
 COPY vscode-luogu.vsix /home/
+RUN chmod +x /home/create_languagepacks.sh
 RUN code-server --install-extension /home/cph-ng-0.5.5.vsix && \
     code-server --install-extension /home/vscode-luogu.vsix && \
     code-server --install-extension ms-ceintl.vscode-language-pack-zh-hans && \