- Bump CLI to ^6.0.0 (#31971)

Summary:
Upgrade CLI to the v6 stable. [Changelog](https://github.com/react-native-community/cli/releases/tag/v6.0.0)

## Changelog

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[General] [Fix] - Bump CLI to ^6.0.0

Pull Request resolved: https://github.com/facebook/react-native/pull/31971

Test Plan: cc kelset grabbou

Reviewed By: TheSavior

Differential Revision: D30158170

Pulled By: ShikaSD

fbshipit-source-id: 392e22cb112a830778149b4a2b4a19198facf42b