chore(deps-dev): bump serve-handler from 6.1.3 to 6.1.5

Bumps [serve-handler](https://github.com/zeit/serve-handler) from 6.1.3 to 6.1.5.
- [Release notes](https://github.com/zeit/serve-handler/releases)
- [Commits](vercel/serve-handler@6.1.3...6.1.5)

---
updated-dependencies:
- dependency-name: serve-handler
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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