Add Ability To Extend / Update Generated Webpack Config

[sghoweri]

Jira

N/A

Summary

Adds a new configureWebpack advanced config option to the Bolt Build Tools .boltrc config to allow extending the default Webpack config generated with additional plugins, module configs, etc via weback-merge.

Details

• This was requested by @christophersmith262 as part of the ongoing Drupal theming improvements work.

How to test

• Test adding a new plugin to the Webpack build to confirm this small addition is working as expected.

[sghoweri]

Thanks @christophersmith262!