Add missing CUJs to PromptViewModelTest

Adds tests for error to unlock / error to success CUJs. Also moves check
in conditional tests so that tests do not start unless condition is met

Flag: NONE TEST_ONLY
Fixes: 348889898
Test: atest PromptViewModelTest
Change-Id: I6602cb0147adb3ca7dac07a7fa132923ed87e60f
1 file changed