ci.freedombox.org: Links to logs broken

The links to the logs for freedombox-testing and freedombox-dev builds are broken. For example, the first link points to https://ftp.freedombox.org/pub/freedombox/logs/a20-olinuxino-lime-freedombox-testing.log, but the actual log is at https://ftp.freedombox.org/pub/freedombox/logs/a20-olinuxino-lime-testing.log.