Update SettingsRoboTests for truth 0.42

SubjectFactory has been replaced with Subject.Factory.

Subject.getDisplaySubject has been replaced with
actualCustomStringRepresentation.

Bug: 130435731
Test: m checkbuild
Change-Id: I2799badfb79432ec70cb928b77294d6940cfc019
Merged-In: I32cb2fcf6094675f79d2fc24702ef6298a9691e4
1 file changed