`Bug`: Properly wait for first opus-frame to be available

[Shirkanesi]

Currently the YTDLPAudioTrack has a pretty ugly way of testing if (the start of) an audio-track has been pulled.
This should be fixed (as stated in line 212 Fixme: Temporary fix to really make sure enough data is present. This must change!)

[Shirkanesi]

This issue is less severe than initially thought.
It only occurs with realy long audio-tracks and only iff those are the first one played.
If there is currently another track scheduled, there will be plenty of time to load the initial frame and no problem will happen.