Product variation collection should display translatable product variation type

@sergei_brill: Kinda tricky to modify the constructor arguments like this, but well, that should only be a problem for people extending the list builder.

Instead of having a $productVariationTypeStorage, let's just inject/use the entity type manager in case we need to get a different storage later too.

Committed, thank you!

@jsacksick Good note about the backward compatibility. But you made release with this issue so fast so, I couldn't fix it in time :)
Just in case you want to keep \Drupal\commerce_product\ProductVariationListBuilder compatible with previous versions of commerce 2, there is one more MR.
PS Commit it to 8.x-2.x only, 3.0.x may have BC breaks, I think.

Automatically closed - issue fixed for 2 weeks with no activity.