bug#58308: guix import -r swallows errors

[Ricardo Wurmus]

Consider this:

   $ ./pre-inst-env guix import elpa -r syslog
   $ echo $?
   0

And now this:

   $ ./pre-inst-env guix import elpa syslog
   guix import: error: failed to download package 'syslog'
   $ echo $?
   1

The recursive importer swallows the error.

-- 
Ricardo