prop_studio: Prevent resource load in case the resource doesn't exists

Author: H2xDev

addons/godotvmf/entities/prop_studio.gd

@@ -29,6 +29,7 @@ func _entity_setup(_entity: VMFEntity) -> void:
 
 			VMFLogger.warn("Model not found: " + model_path);
 			VMFCache.add_logged_file(model);
+			return;
 
 		model_scene = ResourceLoader.load(model_path) as PackedScene;
 		VMFCache.add_cached(model, model_scene);