chore(deps): bump nokogiri from 1.13.9 to 1.15.6

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.13.9 to 1.15.6.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.13.9...v1.15.6)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-type: indirect
...

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