LibJS+LibWeb: Wrap raw JS::Cell*/& fields in GCPtr/NonnullGCPtr

Author: https://github.com/mattco98
Commit: 7c0c1c8f49
Pull-request: https://github.com/SerenityOS/serenity/pull/17743
Reviewed-by: https://github.com/linusg ✅

Userland/Libraries/LibJS/Runtime/PromiseResolvingFunction.h

@@ -40,8 +40,8 @@ private:
 
     virtual void visit_edges(Visitor&) override;
 
-    Promise& m_promise;
-    AlreadyResolved& m_already_resolved;
+    NonnullGCPtr<Promise> m_promise;
+    NonnullGCPtr<AlreadyResolved> m_already_resolved;
     FunctionType m_native_function;
 };