### Godot version

4.2 247c354

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

#75778 exposed `_validate_property()` to scripting. It's implemented in GDScript and C#, but not GDExtension (depends on #78634).
https://github.com/godotengine/godot/blob/247c3548d810136ffe9c1694cd76db3236efaa90/core/object/script_language_extension.h#L685-L687

Relevant discussion: https://github.com/godotengine/godot/pull/75778#discussion_r1307294940

### Steps to reproduce

1. Add GDExtension script
2. Use `_validate_property()`

### Minimal reproduction project

N/A
Object *o = (Object *)p_object;
	o->set_instance_binding(p_token, p_binding, p_callbacks);
}
static void gdextension_object_set_instance(GDExtensionObjectPtr p_object, GDExtensionConstStringNamePtr p_classname, GDExtensionClassInstancePtr p_instance) {
	const StringName classname = *reinterpret_cast<const StringName *>(p_classname);
	Object *o = (Object *)p_object;
	ClassDB::set_object_extension_instance(o, classname, p_instance);
}
static GDExtensionObjectPtr gdextension_object_get_instance_from_id(GDObjectInstanceID p_instance_id) {
	return (GDExtensionObjectPtr)ObjectDB::get_instance(ObjectID(p_instance_id));
}
static GDExtensionBool gdextension_object_get_class_name(GDExtensionConstObjectPtr p_object, GDExtensionClassLibraryPtr p_library, GDExtensionUninitializedStringNamePtr r_class_name) {
	if (!p_object) {
		return false;
	}
	const Object *o = (const Object *)p_object;
	memnew_placement(r_class_name, StringName);
	StringName *class_name = reinterpret_cast<StringName *>(r_class_name);
	*class_name = o->get_class_name_for_extension((GDExtension *)p_library);
	return true;
}
static GDExtensionObjectPtr gdextension_object_cast_to(GDExtensionConstObjectPtr p_object, void *p_class_tag) {
	if (!p_object) {
		return nullptr;
	}
	Object *o = (Object *)p_object;
	return o->is_class_ptr(p_class_tag) ? (GDExtensionObjectPtr)o : (GDExtensionObjectPtr) nullptr;
}
static GDObjectInstanceID gdextension_object_get_instance_id(GDExtensionConstObjectPtr p_object) {