Feature: support webpack v5 stats

[davidhouweling]

At present webpack-bundle-delta only supports webpack v4. As webpack v5 has been our for a few months now we need to look at adding support for it.

Based on initial investigations the following likely cause of action needs to be taken:

• Use package alias remapping to rename the present webpack to webpack 4 as well as @types/webpack
• Webpack 5 does comes with types, however it doesn't have stats types, so we need to create a PR for webpack itself to output the stats defintions, making sure the stats are aligned
• Consumed the new version of webpack which would contain the stats
• Update WBD code to logically work out what to do given each version that is passed to it

[davidhouweling]

Webpack PR to restore ability to get types for webpack 5: webpack/webpack#12228