Summary

This change does 3 things:

• Adds a package reference for Microsoft.Build.Utilities.Core 17.0.0 to the AppSettingStronglyTyped.Test project. Without this change, the test project does not build. The AppSettingStronglyTyped project already references this package.
• Updates the project type GUID for the test project. (Visual Studio made this change automatically.) See this for details.
• Fixes lib instead of tasks #5665. Changing lib to tasks is one way to fix the issue of the task not loading; however, documentation for this sample suggests a better solution.