Jonathan Brielmaier 8488f45b6e
Revert "system: Assert, that user and group names are unique."
This reverts commit a3002104a84c60556b6616d100cb98019e48759d, which
breaks certain system configurations like:

$ guix system reconfigure config.scm
guix system: error: the following groups appear more than once: lp
2021-01-12 23:53:53 +01:00
..
2021-01-12 17:43:41 -05:00
2020-12-03 12:36:03 +01:00
2021-01-12 14:40:36 +03:00