CI: deploy OpenShift-based 5GC through CoreNetwork, use in Ping/Iperf

- Use scripts to deploy OpenShift-based 5GC in ci_infra.yaml
- Use for oc-cn5g, oc-cn5g-20897, and oc-cn5g-20897-aerial2
  for (un)deployment, ping, iperf in relevant XML files
- Convert hardcoded IP addresses to %cn_ip%

ci-scripts/scripts/oc-cn5g-undeploy.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+set -e
+
+function die() { echo $@; exit 1; }
+[ $# -eq 2 ] || die "usage: $0 <path-to-dir> <namespace>"
+
+OC_DIR=${1}
+OC_NS=${2}
+
+cat ${OC_DIR}/oc-password | oc login -u oaicicd --server https://api.oai.cs.eurecom.fr:6443 > /dev/null
+oc project ${OC_NS} > /dev/null
+helm uninstall oai5gcn --wait
+oc logout > /dev/null