armband deploy: switch to local Ubuntu/MOS mirrors

armband deploy: switch to local Ubuntu/MOS mirrors

Since we now enabled local (multiarch) mirrors for Ubuntu, we
should make the automatic deploy benefit from them, and not
rely on public internet mirros at all.

FIXME: completely remove repo overrides and let dea_base set
these approapiately, after the packetary mirror rework is
merged in Fuel@OPNFV (FUEL-223).

JIRA: ARMBAND-35
JIRA: FUEL-218
JIRA: FUEL-223

Change-Id: I424fff2ec89b38a6e3a911a6287add34c64633c9
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
(cherry picked from commit 26c26dc9e51d722325d1ca6f76678bb1531213d3)