Document Read-Host new parameter called MaskInput

[davinci26]

Documentation Issue

Add documentation for the new parameter of Read-Host that was introduced in PowerShell/PowerShell#10908

Context of the issue

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  Cmdlet reference & about_ topics

  • Version 7 content
  • Version 6 content
  • Version 5.1 content

  Conceptual articles

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Detailed description of the issue

[iSazonov]

From @PaulHigin

This will be unsupported over remoting for now, since it involves protocol changes.