Fix bug : Rename class OnKeyDownHook

OnKeyDownHook wasn't usable in unity because the name was no longer matching the file name

Runtime/Hooks/OnKeyDownHook.cs

 
 namespace GameplayIngredients.Hooks
 {
-    public class OnKeyDownAction : HookBase
+    public class OnKeyDownHook : HookBase
     {
         public enum ActionType
         {