Bump atom in /examples/vendored/complicated_cargo_library

Bumps [atom](https://github.com/slide-rs/atom) from 0.3.5 to 0.3.6.
- [Release notes](https://github.com/slide-rs/atom/releases)
- [Commits](https://github.com/slide-rs/atom/commits)

---
updated-dependencies:
- dependency-name: atom
  dependency-type: indirect
...

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