message: docs: fix readme workflow shield
diff: A customizable cross-platform graphical process/system monitor for the terminal.<br />Supports Linux, macOS, and Windows. Inspired by <a href=https://github.com/aksakalli/gtop>gtop</a>, <a href=https://github.com/xxxserxxx/gotop>gotop</a>, and <a href=https://github.com/htop-dev/htop/>htop</a>.
  </p>
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  +[<img src="https://img.shields.io/github/actions/workflow/status/ClementTsang/bottom/ci.yml?branch=master&style=flat-square&logo=github" alt="CI status">](https://github.com/ClementTsang/bottom/actions?query=branch%3Amaster)
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