Fixes a bug whereby GuixSD would create the /nonexistent directory, from
user 'nobody', even though it has 'create-home-directory?' set to #f.
* gnu/build/activation.scm (activate-users+groups): Add comment for
\#:create-home?.
(activate-user-home)[ensure-user-home]: Skip when CREATE-HOME? is #f or
SYSTEM? is #t.
* gnu/tests/base.scm (run-basic-test)["no extra home directories"]: New
tests.
41f76ae08a