Fixed tests based on return value of PIN length

This CL aims at fixing the tests in Settings due to the fact that
earlier PIN length was being returned as a long whereas now it's being
returned as an integer now.

Bug: b/267222046
Test: atest AutoPinConfirmPreferenceControllerTest
Change-Id: Iee28557e25a411c2ce6a6245afaafb890b753261