GitLab

- Mostly reduce indentation
- Use RQL parameter for CubicWeb cache

- Use `sh` of `bash`, because it is more common
  (`bash` may not be installed in favor of `zsh` or `fish`)
- Better management of number of arguments
- Redirect error messages to `stderr`
- Manage the empty argument case
- Protect use of the argument with double quotes

This should improve performance on instances with
large amounts of relations per entity.

This does not apply when onlyConfiguredEntityTypes is true.
In this case the order in which entities are configured is still used.

See https://github.com/marmelab/react-admin/issues/7829

Relations can still be shown manually using configuration

Only in show and list views