build(deps-dev): bump stylelint and stylelint-config-twbs-bootstrap (#…

…1610)

Bumps [stylelint](https://github.com/stylelint/stylelint) and [stylelint-config-twbs-bootstrap](https://github.com/twbs/stylelint-config-twbs-bootstrap). These dependencies needed to be updated together.

Updates `stylelint` from 14.16.1 to 15.2.0
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@14.16.1...15.2.0)

Updates `stylelint-config-twbs-bootstrap` from 7.0.0 to 8.0.0
- [Release notes](https://github.com/twbs/stylelint-config-twbs-bootstrap/releases)
- [Commits](twbs/stylelint-config-twbs-bootstrap@v7.0.0...v8.0.0)

---
updated-dependencies:
- dependency-name: stylelint
  dependency-type: direct:development
  update-type: version-update:semver-major
- dependency-name: stylelint-config-twbs-bootstrap
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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