* Update JS dependencies
- Update all JS dependencies
- Adapt webpack config for version 5
- Update to Less 4.0, adapting usage of removed mixin syntax
- Enable new ESLint rules and fix discovered issues
* update license-webpack-plugin to fix missing licenses
* update license-webpack-plugin once more to get webpack into the license output
* switch to license-checker-webpack-plugin again for performance
* update deps again
Co-authored-by: Lauris BH <lauris@nix.lv>
