Bumps [sinon](https://github.com/sinonjs/sinon) from 7.2.4 to 7.2.6.
- [Release notes](https://github.com/sinonjs/sinon/releases)
- [Changelog](https://github.com/sinonjs/sinon/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sinonjs/sinon/compare/v7.2.4...v7.2.6)
Signed-off-by: dependabot[bot] <support@dependabot.com>