[vcpkg] Bootstrap should use Get-CimInstance instead of Get-WmiObject.

[TheGoddessInari]

This lets it work with both Powershell 5.x and Powershell Core 6.0.

It's not clear if Powershell 7.0 will remain compatible for other reasons.

[ras0219-msft]

Thanks for the PR!

Also, looks like it's available down to 3.0[1] (the earliest version listed in the docs). However, we need testing to ensure this is available for Windows 7, which iirc has 2.0 by default.

[1] https://docs.microsoft.com/en-us/powershell/module/cimcmdlets/get-ciminstance?view=powershell-3.0

[TheGoddessInari]

Would it be better to have a version check for Powershell 2 and opt to fall back to use WMIObject in that case?

[Rastaban]

@TheGoddessInari that sounds good, could you add the logic to fall back for 2.0?