LibJS: Make Script.h not include AST.h

Author: https://github.com/awesomekling
Commit: 65e7c58990
Pull-request: https://github.com/SerenityOS/serenity/pull/16153
Reviewed-by: https://github.com/linusg

Userland/Libraries/LibJS/Forward.h

@@ -184,6 +184,7 @@ class ObjectEnvironment;
 class Parser;
 struct ParserError;
 class PrimitiveString;
+class Program;
 class PromiseCapability;
 class PromiseReaction;
 class PropertyAttributes;