Add support for muting microphone

[uezo]

Stop capturing data from microphone when muted. UnityEngine.Microphone ends internally.

var microphone = GetComponent<ChatdollMicrophone>();

// Mute
microphone.SetMute(true);

// Unmute
microphone.SetMute(false);

// Toggle
microphone.ToggleMute();

Also remove ChatdollMicrophone.IsUpdateOnThisFrame to detect silence to control recording session even no frame data comes from microphone.