build(deps-dev): bump the npm_and_yarn group with 1 update

Bumps the npm_and_yarn group with 1 update: [vuepress](https://github.com/vuejs/vuepress/tree/HEAD/packages/vuepress).


Updates `vuepress` from 2.0.0-rc.8 to 2.0.0-rc.9
- [Release notes](https://github.com/vuejs/vuepress/releases)
- [Changelog](https://github.com/vuejs/vuepress/blob/master/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vuepress/commits/HEAD/packages/vuepress)

---
updated-dependencies:
- dependency-name: vuepress
  dependency-type: direct:development
  dependency-group: npm_and_yarn-security-group
...

Signed-off-by: dependabot[bot] <support@github.com>