build(deps): Bump external/imgui-filebrowser from 980a444 to 66e77e9

Bumps [external/imgui-filebrowser](https://github.com/AirGuanZ/imgui-filebrowser) from `980a444` to `66e77e9`.
- [Commits](AirGuanZ/imgui-filebrowser@980a444...66e77e9)

---
updated-dependencies:
- dependency-name: external/imgui-filebrowser
  dependency-type: direct:production
...

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