Bump traitlets from 5.2.0 to 5.2.1.post0 (#1812)
Bump traitlets from 5.2.0 to 5.2.1.post0 (#1812)

Bumps [traitlets](https://github.com/ipython/traitlets) from 5.2.0 to 5.2.1.post0.
- [Release notes](https://github.com/ipython/traitlets/releases)
- [Commits](https://github.com/ipython/traitlets/compare/5.2.0...5.2.1.post0)

---
updated-dependencies:
- dependency-name: traitlets
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
KlubJagiellonski/pola-backend,KlubJagiellonski/pola-backend,KlubJagiellonski/pola-backend,KlubJagiellonski/pola-backend