Remove Generic from ProjectileImpactEvent (#7959)

Generification of this event was half-done and has been aborted, leaving the generic parameter in place just creates confusion and crashes

src/main/java/net/minecraftforge/event/ForgeEventFactory.java

@@ -624,9 +624,9 @@ public class ForgeEventFactory
         return event.getCharge();
     }
 
-    public static <T extends Projectile> boolean onProjectileImpact(T projectile, HitResult ray)
+    public static boolean onProjectileImpact(Projectile projectile, HitResult ray)
     {
-        return MinecraftForge.EVENT_BUS.post(new ProjectileImpactEvent<>(projectile, ray));
+        return MinecraftForge.EVENT_BUS.post(new ProjectileImpactEvent(projectile, ray));
     }
 
     public static LootTable loadLootTable(ResourceLocation name, LootTable table, LootTables lootTableManager)

src/main/java/net/minecraftforge/event/entity/ProjectileImpactEvent.java

@@ -35,12 +35,12 @@ import net.minecraftforge.eventbus.api.Cancelable;
  * Killing or other handling of the entity after event cancellation is up to the modder.
  */
 @Cancelable
-public class ProjectileImpactEvent<T extends Projectile> extends EntityEvent
+public class ProjectileImpactEvent extends EntityEvent
 {
     private final HitResult ray;
-    private final T projectile;
+    private final Projectile projectile;
 
-    public ProjectileImpactEvent(T projectile, HitResult ray)
+    public ProjectileImpactEvent(Projectile projectile, HitResult ray)
     {
         super(projectile);
         this.ray = ray;
@@ -52,7 +52,7 @@ public class ProjectileImpactEvent<T extends Projectile> extends EntityEvent
         return ray;
     }
 
-    public T getProjectile()
+    public Projectile getProjectile()
     {
         return projectile;
     }