Replace rollup-plugin-cleanup module

To shape a proper `aem.js` (formatting, comments cleanup...), we use [rollup-plugin-cleanup](https://github.com/aMarCruz/rollup-plugin-cleanup) plugin for rollup, but this module has not been touched for 4 years now and starts creating dependencies issues (depends on old `rollup-pluginutils`).
We should find another solution.

The plugin is used for: (see config https://github.com/adobe/aem-lib/blob/main/rollup.config.js#L49-L52)
- make sure `aem.js` passes the `aem-boilerplate` linting rules (including: keep eslint instructions, remove `//` comments, line breaks, indentation)
- do not duplicate license comments (only one license at the beginning of the concatenated file)
- get rid of `c8` comments