FEnhancedActionKeyMapping struct has incorrect comparison results

The fix for this is to override the  FEnhancedActionKeyMapping::operator== to account for the deep copy that happens on modifiers instead of comparing addresses

1. When rebuilding mapping contexts, a deep copy of each input mapping is done, which creates a whole new instance of the modifiers with a different addresses than the original.
2. Later on when the mappings are compared for equality, their modifiers have different addresses and are treated as different even though its a direct copy of that mapping