Fix import of multiple Audio files at once

[Banane9]

Adds a fix for Yellow-Dog-Man/Resonite-Issues#737

[Nytra]

How is this different from the original? The only part I can see that is different is var audioTypeGroup = await UniversalImporter.DetectAudioTypeGroup(audioPlayerInterface.Clip.Target.Target); which wouldn't change much I think

[Banane9]

Oops, just saw approved in the emails and thought it was both :'D

The difference is that audioPlayerInterface.Clip.Target.Target actually has the clip, while the slot.GetComponentInChildren<IAssetProvider>() in the original doesn't work.
I'm not exactly sure why, but I tested it not working before and working after the change.

[Nytra]

Oh it's because SpawnEntity does not specify an assets slot, so they go to the world assets slot instead