### 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
GDExtensionInitializationLevel minimum_initialization_level;
	
	void *userdata;
	
	void (*initialize)(void *userdata, GDExtensionInitializationLevel p_level);
	void (*deinitialize)(void *userdata, GDExtensionInitializationLevel p_level);
} GDExtensionInitialization;
typedef void (*GDExtensionInterfaceFunctionPtr)();
typedef GDExtensionInterfaceFunctionPtr (*GDExtensionInterfaceGetProcAddress)(const char *p_function_name);
/*
 * Each GDExtension should define a C function that matches the signature of GDExtensionInitializationFunction,
 * and export it so that it can be loaded via dlopen() or equivalent for the given platform.
 *
 * For example:
 *
 *   GDExtensionBool my_extension_init(GDExtensionInterfaceGetProcAddress p_get_proc_address, GDExtensionClassLibraryPtr p_library, GDExtensionInitialization *r_initialization);
 *
 * This function's name must be specified as the 'entry_symbol' in the .gdextension file.
 *
 * This makes it the entry point of the GDExtension and will be called on initialization.
 *
 * The GDExtension can then modify the r_initialization structure, setting the minimum initialization level,
 * and providing pointers to functions that will be called at various stages of initialization/shutdown.
 *
 * The rest of the GDExtension's interface to Godot consists of function pointers that can be loaded
 * by calling p_get_proc_address("...") with the name of the function.
 *
 * For example:
 *
 *   GDExtensionInterfaceGetGodotVersion *get_godot_version = (GDExtensionInterfaceGetGodotVersion)p_get_proc_address("get_godot_version");