### 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
return (GDExtensionPtrOperatorEvaluator)Variant::get_ptr_operator_evaluator(Variant::Operator(p_operator), Variant::Type(p_type_a), Variant::Type(p_type_b));
}
static GDExtensionPtrBuiltInMethod gdextension_variant_get_ptr_builtin_method(GDExtensionVariantType p_type, GDExtensionConstStringNamePtr p_method, GDExtensionInt p_hash) {
	const StringName method = *reinterpret_cast<const StringName *>(p_method);
	uint32_t hash = Variant::get_builtin_method_hash(Variant::Type(p_type), method);
	if (hash != p_hash) {
		ERR_PRINT_ONCE("Error getting method " + method + ", hash mismatch.");
		return nullptr;
	}
	return (GDExtensionPtrBuiltInMethod)Variant::get_ptr_builtin_method(Variant::Type(p_type), method);
}
static GDExtensionPtrConstructor gdextension_variant_get_ptr_constructor(GDExtensionVariantType p_type, int32_t p_constructor) {