avoid using Various Artists when not all providers use it

[UltimateRiff]

I just recently imported a single (permalink) with release 4 artists and found that Spotify gave the release artist as "Various Artists", yet all other providers listed out all the artists.

I seem to remember seeing somewhere that Spotify does this, but I can't say for certain if they do this in general or not. either way, I think Harmony should err on the side of crediting the artists listed rather than Various Artists, at least in cases like this

[quantenzitrone]

beatport lists all artists for collections, so this has to be a spotify specific thing
e.g. https://www.beatport.com/release/hardwave-chapter-3/4319435

[UltimateRiff]

could be Spotify specific in this case, but I think it'd be good to have this logic for other cases that come up down the road