Update lerna requirement from 3.14.1 to 3.15.0
Update lerna requirement from 3.14.1 to 3.15.0

Updates the requirements on [lerna](https://github.com/lerna/lerna/tree/HEAD/core/lerna) to permit the latest version.
- [Release notes](https://github.com/lerna/lerna/releases)
- [Changelog](https://github.com/lerna/lerna/blob/master/core/lerna/CHANGELOG.md)
- [Commits](https://github.com/lerna/lerna/commits/v3.15.0/core/lerna)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
medanat/eslint-config