Strings
'invalid age' is illegal in Java. Single quotes are used for a single character. As you note,d you have to use "invalid age" to make Java happy regarding syntax.
Console
The behavior is correct. JUnit is catching the exception so you don't see it on the console.
Convention
Java convention is to use camel case for classnames. Beginning with an uppercase letter. So it would be better if your class was named PersonTest.