Webpack task options should be split from webpack config overrides

[christiango]

The options to the webpack task achieve 2 things:

1. Configures things for the actual just task (nodeArgs, path to config file)
2. Passes generic overrides to the webpack config

This resulted in a bug that is addressed in #174, but we need a better long term solution, such as putting the config overrides under a configOverrides property on the task config

[github-actions]

Issues seem to have gone stale.

[ecraig12345]

This still seems like a valid issue. Combining webpack and non-webpack options in the same object is strange.