Restore Webpack bundle analyzer functionality

[drewbo]

Webpack bundle analyzer is currently commented out in out webpack configuration but uncommenting it (and adding it to plugins) doesn't show the results at localhost:8888 in the docker compose build. It will work on local builds. Investigate how to add this functionality back.

Notes

• https://github.com/cloud-gov/pages-core/blob/main/webpack.config.js#L6
• https://github.com/cloud-gov/pages-core/blob/main/docker-compose.yml#L23

Acceptance Criteria

• Operators can view bundle analysis at localhost:8888 when running docker compose