Fixed example code in zh documentation.

docs/manual/zh/introduction/Loading-3D-models.html

@@ -75,7 +75,7 @@
 	</p>
 
 	<code>
-		import { GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader';
+		import { GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader.js';
 	</code>
 
 	<p>
@@ -84,7 +84,7 @@
 	</p>
 
 	<code>
-		var loader = new THREE.GLTFLoader();
+		var loader = new GLTFLoader();
 
 		loader.load( 'path/to/model.glb', function ( gltf ) {