Bump theme-ui from 0.16.2 to 0.17.2

Bumps [theme-ui](https://github.com/system-ui/theme-ui) from 0.16.2 to 0.17.2.
- [Release notes](https://github.com/system-ui/theme-ui/releases)
- [Changelog](https://github.com/system-ui/theme-ui/blob/v0.17.2/CHANGELOG.md)
- [Commits](system-ui/theme-ui@v0.16.2...v0.17.2)

---
updated-dependencies:
- dependency-name: theme-ui
  dependency-version: 0.17.2
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]