Nextcloud 13.0.3 and 12.0.8 available

[LEDfan]

Seems like the push for the 13.0.3 release was stopped (https://github.com/nextcloud/updater_server/commit/313f1ff152f57d3975bbd438d489834d04c0a788) due to https://github.com/nextcloud/server/pull/9802 .