[IEC][SEBA] Move to the new SEBA version in CI

The work for upgrading our IEC SEBA version for arm64 to the latest stable is nearly complete. For this effort we have employed the use of upstream Opencord tools for deploying SEBA (specifically SEBA-in-a-Box), by means of forking the automation-tools and helm-charts repositories from Opencord. The longer term goal is to also integrate arm64 support in upstream, so that forking is not necessary, but that is another subject.

Currently, the Akraino CI still uses the old version of SEBA in the corresponding job:
https://jenkins.akraino.org/view/iec/job/iec-type2-install-seba_on_arm-fuel-virtual-ubuntu1804-daily-master/

We need to complete the switch to the new version by modifying the installation script:
https://gerrit.akraino.org/r/gitweb?p=iec.git;a=blob;f=src/use_cases/seba_on_arm/install/install.sh;h=f489c03278d4ce7b1ba407371fec93b4d84ea4c5;hb=HEAD

The method used instead will be the same proposed in my previous change (WIP) which installed PONSim:
https://gerrit.akraino.org/r/c/ci-management/+/1243

The main difference to this gerrit change will be that we will no longer assume SEBA has been previously installed by some other means, and instead we will explicitly rely on the installation script to deploy SEBA, specifically this slightly altered version of SEBA-in-a-Box which, compared to the established meaning in Opencord, is able to run on 3-node clusters running the IEC platform.