[usecase] Update usecase for SpeechSynthesis

Impacted tests(approved): new 0, update 1, delete 0
Unit test platform: [IVI]
Unit test result summary: pass 1, fail 0, block 0
Merge pull request #1411 from kangxu/kangxu/usecase/SpeechSynthesis/update

[usecase] Update usecase for SpeechSynthesis