build(deps): bump tiktoken-rs from 0.5.8 to 0.5.9

Bumps [tiktoken-rs](https://github.com/zurawiki/tiktoken-rs) from 0.5.8 to 0.5.9.
- [Release notes](https://github.com/zurawiki/tiktoken-rs/releases)
- [Commits](zurawiki/tiktoken-rs@v0.5.8...v0.5.9)

---
updated-dependencies:
- dependency-name: tiktoken-rs
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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