Add unit tests for all the validation

[ptorr-msft]

[buddhikac96]

Do you prefer making a unit test library or just a unit test file?

[ptorr-msft]

Hi, thanks for your interest! I think a unit test library (UWP Unit Test) would be best. Would you like me to assign this to you?

[buddhikac96]

Totally okay for me. But I am a beginner. So just do only if it is necessary for the project 😃