Jenkinsfile: load groovy code in each node
Jenkinsfile: load groovy code in each node

If we allocate a node to checkout the code that we use to run the
parallel jobs later on, that node will stay busy until the end of the
whole pipeline, a waste of resources.

Signed-off-by: Tobias Olausson <e5abfa285347082f76013504c37f988d1046765a@pelagicore.com>

DunderRoffe/pelux-manifests,sashko/pelux-manifests,Pelagicore/pelux-manifests