Remove unused dependency

src/packager/packager.js

@@ -5,7 +5,6 @@ import {readAsArrayBuffer, readAsURL} from './lib/readers';
 import largeAssets from './large-assets';
 import xhr from './lib/xhr';
 import pngToAppleICNS from './lib/icns';
-import deepClone from './lib/deep-clone';
 
 const escapeXML = (v) => v.replace(/["'<>&]/g, (i) => {
   switch (i) {