Identity: Update requirements about SessionTranscript CBOR and provisioning challenge.

Bug: 156911917
Bug: 158107945
Test: atest VtsHalIdentityTargetTest
Test: atest android.security.identity.cts
Merged-In: Iacdf89744bbd30c5a10d6cba873147e424ddb01b
Change-Id: I06a536425975b2a5ac7a6adc7bcec9645c370e79
2 files changed