defaults: Build 18.12 images only once per week
Now that 18.12.0 has been released there's no need for daily builds.
Signed-off-by: Emanuele Aina emanuele.aina@collabora.com
Now that 18.12.0 has been released there's no need for daily builds.
Signed-off-by: Emanuele Aina emanuele.aina@collabora.com