Bug 9260: stop koha-run-backups complaining "missing ]"

Bug 9260: stop koha-run-backups complaining "missing ]"

Found because cron.daily/koha output contains the error "[: 97: missing ]"

To test:

  1. run koha-run-backups --days 2 --output /var/spool/koha
  2. should see no output

Sponsored-by: Library of the Józef Piłsudski Institute of America
Signed-off-by: Vitor FERNANDES <vfernandes@keep.pt>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
I still get an error:
  ./koha-run-backups: 58: ./koha-run-backups: koha-list: not found
But this patch fixes the syntax error
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>