Obsolete _rebootRequested with _restartRequired

### Prerequisites

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- [x] Make sure you are able to repro it on the latest version
- [x] Search the existing issues.

### Summary

The canonical docs still reference the obsolete property instead of the new paradigm.

https://learn.microsoft.com/en-us/powershell/dsc/reference/schemas/resource/properties/overview?view=dsc-3.0#_rebootrequested
