### Godot version

4.0.dev (f581f21dd61a8fb581b80d07755cdf60c95d146d)

### System information

Windows 10 - Ryzen 7 - 4070ti

### Issue description

When using the threaded resource loader, textures on materials are lost.

This is the scene being loaded in the IDE:
![image](https://github.com/godotengine/godot/assets/1945449/232dd16b-81c4-49cf-a980-3efcfa97ff79)

This is the result in runtime:
![image](https://github.com/godotengine/godot/assets/1945449/235176d3-6058-4bed-8fbe-cad14a5e0d32)


### Steps to reproduce

Use code such as the following to load a scene:
```
func _load_scene(p_scene_path):
	var new_scene : PackedScene
	if ResourceLoader.has_cached(p_scene_path):
		# Load cached scene
		new_scene = ResourceLoader.load(p_scene_path)
	else:
		# Start the loading in a thread
		ResourceLoader.load_threaded_request(p_scene_path)

		# Loop waiting for the scene to load
		while true:
			var progress := []
			var res := ResourceLoader.load_threaded_get_status(p_scene_path, progress)
			if res != ResourceLoader.THREAD_LOAD_IN_PROGRESS:
				break;

			_progress_bar = progress[0]
			await get_tree().create_timer(0.1).timeout

		# Get the loaded scene
		new_scene = ResourceLoader.load_threaded_get(p_scene_path)
	
	$CanvasLayer.visible = false
	add_child(new_scene.instantiate())
```

Now create a scene to load that has a material with a texture.

### Minimal reproduction project

[TestResourceLoader.zip](https://github.com/godotengine/godot/files/11549692/TestResourceLoader.zip)

shader_names->heightmap_texture_channel = "heightmap_texture_channel";
	shader_names->refraction_texture_channel = "refraction_texture_channel";
	shader_names->transmittance_color = "transmittance_color";
	shader_names->transmittance_depth = "transmittance_depth";
	shader_names->transmittance_boost = "transmittance_boost";
	shader_names->texture_names[TEXTURE_ALBEDO] = "texture_albedo";
	shader_names->texture_names[TEXTURE_METALLIC] = "texture_metallic";
	shader_names->texture_names[TEXTURE_ROUGHNESS] = "texture_roughness";
	shader_names->texture_names[TEXTURE_EMISSION] = "texture_emission";
	shader_names->texture_names[TEXTURE_NORMAL] = "texture_normal";
	shader_names->texture_names[TEXTURE_RIM] = "texture_rim";
	shader_names->texture_names[TEXTURE_CLEARCOAT] = "texture_clearcoat";
	shader_names->texture_names[TEXTURE_FLOWMAP] = "texture_flowmap";
	shader_names->texture_names[TEXTURE_AMBIENT_OCCLUSION] = "texture_ambient_occlusion";
	shader_names->texture_names[TEXTURE_HEIGHTMAP] = "texture_heightmap";
	shader_names->texture_names[TEXTURE_SUBSURFACE_SCATTERING] = "texture_subsurface_scattering";
	shader_names->texture_names[TEXTURE_SUBSURFACE_TRANSMITTANCE] = "texture_subsurface_transmittance";
	shader_names->texture_names[TEXTURE_BACKLIGHT] = "texture_backlight";
	shader_names->texture_names[TEXTURE_REFRACTION] = "texture_refraction";
	shader_names->texture_names[TEXTURE_DETAIL_MASK] = "texture_detail_mask";
	shader_names->texture_names[TEXTURE_DETAIL_ALBEDO] = "texture_detail_albedo";
	shader_names->texture_names[TEXTURE_DETAIL_NORMAL] = "texture_detail_normal";
	shader_names->texture_names[TEXTURE_ORM] = "texture_orm";
	shader_names->alpha_scissor_threshold = "alpha_scissor_threshold";
	shader_names->alpha_hash_scale = "alpha_hash_scale";
	shader_names->alpha_antialiasing_edge = "alpha_antialiasing_edge";
	shader_names->albedo_texture_size = "albedo_texture_size";
}
HashMap<uint64_t, Ref<StandardMaterial3D>> BaseMaterial3D::materials_for_2d;
void BaseMaterial3D::finish_shaders() {