docs: Voice transcription - addition of known issue
docs: Voice transcription - addition of known issue

Bug: 28836448
Change-Id: Ie5df3860d85ab357ec133142c5a4a58eba02d9fa

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base