Why not supporting an object for webpackConfig parameter?

Now, webpackConfig parameter just supports the file path which is not convenient as an object. So Why not supporting an object for webpackConfig parameter just like the tsConfig parameter?

example:

```js
const tree = dependencyTree({
filename: `xxx/index.tsx`,
directory: `xxx/src`,
filter: (path) => path.indexOf("node_modules") === -1,
webpackConfig: {
resolve: {
extensions: [".js", ".jsx", ".tsx", ".ts"],
},
}
});
```