soundtrigger: Add VTS tests for v2.1

Re-tests the implementation of the inherited methods from v2.0.

Adds tests for the methods introduced in v2.1.

Bug: 68823037
Test: VtsHalSoundtriggerV2_1TargetTest
Change-Id: Iab4d397d2581da1ff9e0d87c7f8d4fa8b483cdd5