Bump yaml and stylelint in /packages/larva-scss

Removes [yaml](https://github.com/eemeli/yaml). It's no longer used after updating ancestor dependency [stylelint](https://github.com/stylelint/stylelint). These dependencies need to be updated together.


Removes `yaml`

Updates `stylelint` from 13.13.1 to 15.6.0
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@13.13.1...15.6.0)

---
updated-dependencies:
- dependency-name: yaml
  dependency-type: indirect
- dependency-name: stylelint
  dependency-type: direct:development
...

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