With the server object to be passed into ping test, it's not necessary
to either hardcode an IP address or provide a template. Instead, always
fill the IP address, which simplies the Ping() code.
Verify that we don't have an IP address/hardcoded by throwing an
assertion.
This is not really used as of now, because most IPs are hardcoded. See
one of the next commits for the use of this.
To make sure that we have the correct IP, there is some code that
verifies that a hardcoded IP and the CN IP would be the same.
Note: need two separate ci_infra.yaml entries, because
- for FlexRIC, the container name is different (is the tutorial CN)
- for RFsim5G E1, we don't have ext-dn => ping UPF
Robert Schmidt