fix(ci): Fix OpenShift DNS node configuration

[astefanutti]

This fixes OpenShift CI workflow.

Release Note

NONE

[astefanutti]

There is still one test TestRunRest/Service_works that fails with:

Caused by: [java.net.UnknownHostException - rest-consumer]: java.net.UnknownHostException: rest-consumer

While it fixes external hostname lookups, it may be the dnsIP setting overrides support for local DNS lookups.

[astefanutti]

It seems a recent update to the ubuntu-latest image brings a newer version of resolvconf, that breaks the existing configuration for the node DNS.

Appending naming servers to openshift.local.clusterup/kubedns/resolv.conf, for external lookups, manages to work-around the issue.

[astefanutti]

After a deeper look, the failure is caused by the Ubuntu upgrade, that now relies on systemd-resolved instead of resolveconf. I've updated the configuration of external DNS servers, and it fixes the OpenShift workflow.

Now the Yaks tests are very flaky. So let's merge this and look at the Yaks tests.