Add unit test coverage for unlock attempts in TrustManagerServiceTest

The downstream effects of an unlock attempt using a pin/password were not
previously tested within the TrustManagerServiceTest. Add these tests in
preparation for further changes to pin/password unlock reporting to
TrustManagerService in b/323086607.

BUG: b/323086607
Test: `atest TrustManagerServiceTest`
Flag: TEST_ONLY
Change-Id: I8ce35a822c807c5e272a5d3169b1bf55499d47e0