Bump axios and @slidev/cli in /docs/slides

Bumps [axios](https://github.com/axios/axios) to 1.6.8 and updates ancestor dependency [@slidev/cli](https://github.com/slidevjs/slidev). These dependencies need to be updated together.


Updates `axios` from 0.21.4 to 1.6.8
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/v1.x/CHANGELOG.md)
- [Commits](axios/axios@v0.21.4...v1.6.8)

Updates `@slidev/cli` from 0.40.16 to 0.48.7
- [Release notes](https://github.com/slidevjs/slidev/releases)
- [Commits](slidevjs/slidev@v0.40.16...v0.48.7)

---
updated-dependencies:
- dependency-name: axios
  dependency-type: indirect
- dependency-name: "@slidev/cli"
  dependency-type: direct:production
...

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