Add option for running ffmpeg_microphone_live as a background process (#32838)
* Add option for running ffmpeg_microphone_live as a background process
* Code quality checks for audio_utils
* Code clean up for audio_utils
* Fixing logic in ffmpeg_microphone calls in audio_utils
* Allowing any arbitrary arguments to be passed to ffmpeg_microphone_live
* Formatting
* Fixing last problems with adding ffmpeg_additional_args
* Fixing default arguments and formatting issues
* Fixing comments for ffmpeg_additional_args
* Adding two shorts tests for ffmpeg_microphone_live
* Fixing test bug