Enable Searching for Pwsh in the "Program Files (Arm)" directory on Windows Arm64

[tsmarvin]

PR Summary

• Begin searching for Pwsh in the "Program Files (Arm)" directory on windows arm64.
  • Note this will only look for the "Program Files (Arm)" directory if the default "Program Files" directory does not contain a PowerShell install.
• Add tests case documenting expected load order.
• Update test cases to refer to v7 instead of v6.
  • I realize that this doesn't actually matter as its just looking for the first integer it finds, but since PS6 has been out of support for several years I thought it was time to update.

PR Checklist

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