Update sinon requirement from ^6.3.5 to ^7.1.1
Update sinon requirement from ^6.3.5 to ^7.1.1

Updates the requirements on [sinon](https://github.com/sinonjs/sinon) to permit the latest version.
- [Release notes](https://github.com/sinonjs/sinon/releases)
- [Changelog](https://github.com/sinonjs/sinon/blob/master/docs/changelog.md)
- [Commits](https://github.com/sinonjs/sinon/commits/v7.1.1)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
hexojs/hexo-cli,hexojs/hexo-cli,hexojs/hexo-cli