build(deps): bump gevent from 22.10.2 to 23.9.0 in /loadtesting (#756)

Bumps [gevent](https://github.com/gevent/gevent) from 22.10.2 to 23.9.0.
- [Release notes](https://github.com/gevent/gevent/releases)
- [Changelog](https://github.com/gevent/gevent/blob/master/docs/changelog_pre.rst)
- [Commits](gevent/gevent@22.10.2...23.9.0)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>