Fixes #2508: Change into backup directory
Fixes #2508: Change into backup directory

This fix ensures that the backup-script will change into the backup directory before running.

Users backup via root user will no longer get a warning, that the script couldn't change into '/root'

zammad/zammad,monotek/zammad,monotek/zammad,monotek/zammad,monotek/zammad,monotek/zammad,monotek/zammad,zammad/zammad,zammad/zammad,zammad/zammad,zammad/zammad,zammad/zammad