rolling_update: run registry auth before upgrading

rolling_update: run registry auth before upgrading

There's some tasks using the new container image during the rolling
upgrade playbook that needs to execute the registry login first otherwise
the nodes won't be able to pull the container image.

Unable to find image 'xxx.io/foo/bar:latest' locally
Trying to pull repository xxx.io/foo/bar ...
/usr/bin/docker-current: Get https://xxx.io/v2/foo/bar/manifests/latest:
unauthorized

Signed-off-by: Dimitri Savineau <dsavinea@redhat.com>
(cherry picked from commit 3f344fdefe02c3b597b886cbef8b7456a7db28eb)