Bump mocha from 1.15.0 to 1.16.0
Bump mocha from 1.15.0 to 1.16.0

Bumps [mocha](https://github.com/freerange/mocha) from 1.15.0 to 1.16.0.
- [Release notes](https://github.com/freerange/mocha/releases)
- [Changelog](https://github.com/freerange/mocha/blob/v1.16.0/RELEASE.md)
- [Commits](https://github.com/freerange/mocha/compare/v1.15.0...v1.16.0)

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

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
alphagov/release,alphagov/release,alphagov/release