PowerToys: Drop unused .NET runtime dependency

[Terrance]

Description

PowerToys is packaged with its own copy of the .NET desktop runtime, and does not require a system installation as well.

Motivation and Context

Fixes #285.

How Has this Been Tested?

Installed, uninstalled and reinstalled locally. PowerToys UI and a handful of tested toys (Awake, Advanced Paste, Find My Mouse) appear to be working as expected.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Migrated package (a package has been migrated from another repository)

Checklist:

• My code follows the code style of this repository.
• My change requires a change to documentation (this usually means the notes in the description of a package).
• I have updated the documentation accordingly (this usually means the notes in the description of a package).
• I have updated the package description and it is less than 4000 characters.
• All files are up to date with the latest Contributing Guidelines
• The added/modified package passed install/uninstall in the chocolatey test environment.
• The changes only affect a single package (not including meta package).

[AppVeyorBot]

❌ Package verification failed, please review the Appveyor Logs and the provided Artifacts before requesting a human reviewer to take a look.

[Terrance]

The build appears to have failed because the CI server can't reach GitHub? (Update config remain unchanged.)

Updating 1 automatic packages at 2025-11-25 21:43:51 (forced)
Push is disabled
NoCheckChocoVersion is disabled
FORCE IS ENABLED. All packages will be updated
   [1/1] powertoys ERROR: 
     au_GetLatest failed 
     The remote server returned an error: (401) Unauthorized. (1.01s)

[Terrance]

@mkevenaar Can you take a look? I can see the last AU for PowerToys built ok so I'm not sure what needs to change here.