Bump prompt-toolkit from 3.0.48 to 3.0.50

Bumps [prompt-toolkit](https://github.com/prompt-toolkit/python-prompt-toolkit) from 3.0.48 to 3.0.50.
- [Release notes](https://github.com/prompt-toolkit/python-prompt-toolkit/releases)
- [Changelog](https://github.com/prompt-toolkit/python-prompt-toolkit/blob/master/CHANGELOG)
- [Commits](https://github.com/prompt-toolkit/python-prompt-toolkit/commits)

---
updated-dependencies:
- dependency-name: prompt-toolkit
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>