[ADI][41/N] remove DEVELOPER_VERIFICATION_BYPASSED_REASON_UNSPECIFIED

This was just for internal invalidation so there is no need to expose it
as an API.

BUG: 360129657
FIXES: 432197722
FLAG: android.content.pm.verification_service
API-Coverage-Bug: 420966373
Test: atest android.content.pm.verify.developer.DeveloperVerificationSessionTest
Test: atest com.android.server.pm.verify.developer.DeveloperVerifierControllerTest

Change-Id: Ic3bffc6d3413e216959f262ea1427405976393a5