call-with-file-lock does not remove lock file

[Ricardo Wurmus]

Hi Guix,

half a year ago I submitted this bug report:
https://issues.guix.gnu.org/57501

“call-with-file-lock” and “call-with-file-lock/no-wait” create a lock
file but don’t remove the lock file when they exit.  The lock on
the file is lifted, but the lock file itself remains behind.

I think we should not litter and remove unused lock files.  What do you
think?

-- 
Ricardo