chore(deps): update xunit to v3

[rhysparry]

This pull request includes updates to the Dirt.Args.Tests project file to change the output type and update package references. The most important changes include modifying the output type from a library to an executable and updating the xUnit package references to their latest versions.

Project configuration changes:

• Dirt.Args.Tests/Dirt.Args.Tests.csproj: Changed the <OutputType> from Library to Exe to ensure the project builds as an executable.

Package updates:

• Dirt.Args.Tests/Dirt.Args.Tests.csproj: Updated the xUnit package references to xunit.v3 version 1.0.0 and xunit.runner.visualstudio version 3.0.0 for compatibility with the latest testing framework.

[rhysparry]

This change is part of the following stack:

• chore(deps): update xunit to v3 #61 ◀

_{Change managed by git-spice.}