transports(daily): use a task to execute callbacks

This commit fixes an issue where we were not waiting for
`asyncio.run_coroutine_threadsafe` to complete which can cause a series of
undesired issues (e.g. not actually executing the coroutine).

CHANGELOG.md

@@ -43,6 +43,9 @@ async def on_audio_data(processor, audio, sample_rate, num_channels):
 
 ### Fixed
 
+- Fixed an issue in `DailyTransport` that would cause some internal callbacks to
+  not be executed.
+
 - Fixed an issue where other frames were being processed while a `CancelFrame`
   was being pushed down the pipeline.