Bump autocannon from 7.14.0 to 7.15.0

Bumps [autocannon](https://github.com/mcollina/autocannon) from 7.14.0 to 7.15.0.
- [Release notes](https://github.com/mcollina/autocannon/releases)
- [Commits](mcollina/autocannon@v7.14.0...v7.15.0)

---
updated-dependencies:
- dependency-name: autocannon
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>