configureBabel(callback, encoreOptions = {}) {
        webpackConfig.configureBabel(callback, encoreOptions);

        return this;
    }
Configure babel, without needing a .babelrc file.

https://babeljs.io/docs/usage/babelrc/

```
Encore.configureBabel(function(babelConfig) {
    // change the babelConfig
    // if you use an external Babel configuration
    // this callback will NOT be used. In this case
    // you can pass null as the first parameter to
    // still be able to use some of the options below
    // without a warning.
}, {
    // set optional Encore-specific options, for instance:

    // change the rule that determines which files
    // won't be processed by Babel
    exclude: /bower_components/

    // ...or keep the default rule but only allow
    // *some* Node modules to be processed by Babel
    includeNodeModules: ['foundation-sites']

    // automatically import polyfills where they
    // are needed
    useBuiltIns: 'usage'

    // if you set useBuiltIns you also have to add
    // core-js to your project using Yarn or npm and
    // inform Babel of the version it will use.
    corejs: 3
});
```

Supported options:
     - {webpack.RuleSetCondition} exclude (default=/(node_modules|bower_components)/)
             A Webpack Condition passed to the JS/JSX rule that
             determines which files and folders should not be
             processed by Babel (https://webpack.js.org/configuration/module/#condition).
             Can be used even if you have an external Babel configuration
             (a babel.config.json file for instance)
             Warning: .babelrc config files don't apply to node_modules. Use
             babel.config.json instead to apply the same config to modules if
             they are not excluded anymore.
             Cannot be used if the "includeNodeModules" option is
             also set.
     - {string[]} includeNodeModules
             If set that option will include the given Node modules to
             the files that are processed by Babel.
             Can be used even if you have an external Babel configuration
             (a babel.config.json file for instance).
             Warning: .babelrc config files don't apply to node_modules. Use
             babel.config.json instead to apply the same config to these modules.
             Cannot be used if the "exclude" option is also set
     - {'usage'|'entry'|false} useBuiltIns (default=false)
             Set the "useBuiltIns" option of @babel/preset-env that changes
             how it handles polyfills (https://babeljs.io/docs/en/babel-preset-env#usebuiltins)
             Using it with 'entry' will require you to import core-js
             once in your whole app and will result in that import being replaced
             by individual polyfills. Using it with 'usage' will try to
             automatically detect which polyfills are needed for each file and
             add them accordingly.
             Cannot be used if you have an external Babel configuration (a .babelrc
             file for instance). In this case you can set the option directly into
             that configuration file.
     - {number|string|object} corejs (default=not set)
             Set the "corejs" option of @babel/preset-env.
             It should contain the version of core-js you added to your project
             if useBuiltIns isn't set to false.

@param {OptionsCallback<object>|null} callback
@param {{exclude?: webpack.RuleSetCondition, includeNodeModules?: string[], useBuiltIns?: 'usage' | 'entry' | false, corejs?: number|string|{ version: string, proposals: boolean }|null}} encoreOptions
@returns {Encore}