In our case UGC items are levels created by players. We want other player's to be able to "like" them. That means that we need to find a way to:
Increment "likes" count on UGC item(level), after a player "likes" it.
Check if player already liked that level(to prevent him from incrementing like count more than once)
Get the list of all levels player liked.
How can we do this by using Playfab?