Rollup is including lodash code inside the ESM build

Since rollup.config.esm.js is configuring "external" as the full lodash library but imports are including specific modules, this config is not taking effect and Rollup is including a large ammount of lodash code in the ESM bundle.

Fixing this configuration reduces bundle size to less than a half, so I think is something good to include. I'll be happy to include this optimization in my projects.