Update JsonAbstract.impl's type (#7154)

This was changed in 400c451a.

std/haxe/display/JsonModuleTypes.hx

@@ -332,7 +332,7 @@ typedef JsonAbstractCast = {
 
 typedef JsonAbstract = {
 	var type: JsonType<Dynamic>;
-	var impl: Null<JsonPath>;
+	var impl: Null<JsonClass>;
 	var binops: Array<JsonAbstractBinop>;
 	var unops: Array<JsonAbstractUnop>;
 	var from: Array<JsonAbstractCast>;
@@ -363,4 +363,4 @@ typedef JsonModuleType<T> = {
 	var args: T;
 }
 
-typedef JsonModuleTypes = Array<JsonModuleType<Dynamic>>;
+typedef JsonModuleTypes = Array<JsonModuleType<Dynamic>>;