Added the interface back to the extension file

loaders/src/glTF/2.0/Extensions/ExtrasAsMetadata.ts

@@ -7,10 +7,13 @@ import { INode, ICamera, IMaterial } from "../glTFLoaderInterfaces";
 import { IGLTFLoaderExtension } from "../glTFLoaderExtension";
 import { GLTFLoader } from "../glTFLoader";
 import { Material } from "babylonjs/Materials/material";
-import { ObjectWithMetadata } from "babylonjs-gltf2interface";
 
 const NAME = "ExtrasAsMetadata";
 
+interface ObjectWithMetadata {
+    metadata: any;
+}
+
 /**
  * Store glTF extras (if present) in BJS objects' metadata
  */