Bump nextra-theme-docs from 2.10.0 to 2.13.4

Bumps [nextra-theme-docs](https://github.com/shuding/nextra) from 2.10.0 to 2.13.4.
- [Release notes](https://github.com/shuding/nextra/releases)
- [Commits](https://github.com/shuding/nextra/compare/nextra-theme-docs@2.10.0...nextra-theme-docs@2.13.4)

---
updated-dependencies:
- dependency-name: nextra-theme-docs
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]