[Portal] Move (unused) readinessImage to global

All helm charts in ONAP are setting readinessImage to global part (it
can then be easy to bump version for everybody at once).

Portal Job is not using it and use a local version.
Move to use global one for consistency

Issue-ID: OOM-2373
Signed-off-by: Sylvain Desbureaux <sylvain.desbureaux@orange.com>
Change-Id: I5400ab595773ffc7111bc43f64c48b7c9a4c2dcd
2 files changed