* less-plugin-clean-css: no updated version.
@wikipedia/less-plugin-clean-css might be an alternative.
* stylelint & stylelint-config-standard
the new versions require configuration and source code changes
nodejs.ensure only sets up NVM if there isn't a system-wide
installation of Node that matches our NODE_MINIMUM_VERSION.
The ubuntu image in the CI comes with an up to date node version,
so pyright from .nvm_packages is never installed.
This commit fixes this by introducing a package.json file.
Alexandre Flament