Don't run pipelines on upstream branches
This was enabled in fd3ce686 to allow linux updating jobs to run on "upstream/" branches. Unfortunately, they never worked as expected since the jobs definition is in a local yaml file which is not available in "upstream/" branches. Those jobs require need rethinking.
Meanwhile, disable pipelines on those branches since there is no value.
Signed-off-by: Dylan Aïssi dylan.aissi@collabora.com