align DISCOVERED event to naming convention

no need for custom event class

Mage.Sets/src/mage/cards/c/CuratorOfSunsCreation.java

@@ -59,7 +59,7 @@ class CuratorOfSunsCreationTriggeredAbility extends TriggeredAbilityImpl {
 
     @Override
     public boolean checkEventType(GameEvent event, Game game) {
-        return event.getType() == GameEvent.EventType.DISCOVER;
+        return event.getType() == GameEvent.EventType.DISCOVERED;
     }
 
     @Override

Mage/src/main/java/mage/abilities/effects/keyword/DiscoverEffect.java

@@ -12,7 +12,7 @@ import mage.filter.FilterCard;
 import mage.filter.common.FilterNonlandCard;
 import mage.filter.predicate.mageobject.ManaValuePredicate;
 import mage.game.Game;
-import mage.game.events.DiscoverEvent;
+import mage.game.events.GameEvent;
 import mage.players.Player;
 import mage.util.CardUtil;
 
@@ -88,7 +88,7 @@ public class DiscoverEffect extends OneShotEffect {
         }
         cards.retainZone(Zone.EXILED, game);
         player.putCardsOnBottomOfLibrary(cards, game, source, false);
-        game.fireEvent(new DiscoverEvent(source, player.getId(), amount));
+        game.fireEvent(GameEvent.getEvent(GameEvent.EventType.DISCOVERED, null, source, player.getId(), amount));
         return card;
     }
 }

Mage/src/main/java/mage/game/events/DiscoverEvent.java

@@ -1,14 +0,0 @@
-package mage.game.events;
-
-import mage.abilities.Ability;
-
-import java.util.UUID;
-
-/**
- * @author Susucr
- */
-public class DiscoverEvent extends GameEvent {
-    public DiscoverEvent(Ability source, UUID playerId, int amount) {
-        super(EventType.DISCOVER, null, source, playerId, amount, false);
-    }
-}

Mage/src/main/java/mage/game/events/GameEvent.java

@@ -539,7 +539,7 @@ public class GameEvent implements Serializable {
          amount      discover value
          flag        not used for this event
          */
-        DISCOVER,
+        DISCOVERED,
         //custom events
         CUSTOM_EVENT
     }