Allow user to edit config dotfiles and not be overwritten

The .bashrc,.profile and .bash_logout files are overwritten every time you launch your Code Builder environment. We recommend that you do not edit these files because your changes will be lost. Instead, create new .bashrc.local,.profile.local and .bash_logout.local files to store your Dotfile customizations.

首先定位 Code Builder 如何创建或覆盖 .bashrc、.profile 和 .bash_logout；issue 未指明入口点或测试。完成的标准是，用户对这些点文件所做的编辑在启动环境后仍然保留，同时所提议的 .bashrc.local、.profile.local 和 .bash_logout.local 文件仍可用于自定义。

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