Fix CI failure after update to PowerShell 7.4.0

[Arlodotexe]

Closes #166

This fixes the CI failures that started to occur after the latest GitHub Actions image update, which updated PowerShell to 7.4.0 LTS by default for ubuntu-22.04.

[Arlodotexe]

We're getting a different error now:

Build started 01/30/[20](https://github.com/CommunityToolkit/Tooling-Windows-Submodule/actions/runs/7718544835/job/21040059522?pr=167#step:9:21)24 22:59:59.
SlnGen : error : Unhandled exception: System.ArgumentException: The value cannot be an empty string. (Parameter 'path')
SlnGen : error :    at System.ArgumentException.ThrowNullOrEmptyException(String argument, String paramName)
SlnGen : error :    at System.IO.Path.GetFullPath(String path)
SlnGen : error :    at System.Linq.Enumerable.SelectEnumerableIterator`2.MoveNext()

The first error could be reproduced locally, but not this one. @michael-hawker any ideas what it could be?

[Arlodotexe]

Looks like that did the trick 🎉