Reduce artifact expiration

Currently ci-flatdeb-builder sets 3d as default artifact expiration, requiring an important storage size. Having those artifacts for so much time brings no value, since the outcome is published in an external server and the latest artifacts are kept thanks to Gitlab's keep artifacts from most recent successful jobs setting.

To reduce the storage requirements, reduce artifact expiration to 1 day, the same use in apertis-image-recipes.

https://phabricator.apertis.org/T9989

Signed-off-by: Walter Lozano walter.lozano@collabora.com