generate proper hostname for a self-signed SSL certificate

[tarzanek]

If you don't use proper hostname, then only this cqlshrc will work: https://github.com/scylladb/scylla-ansible-roles/blob/master/ansible-scylla-node/templates/cqlshrc.j2#L11

However validate=true won't work, until self signed certificates are properly generated Currently it is disabled and we explicitly pass on map of hostnames to certs, but this can be likely improved. Let's investigate if this is possible, ev. improve this state

[vladzcloudius]

@tarzanek It's not clear what's the context of this issue:

• What didn't work?
• How to reproduce?

[tarzanek]

the goal is to be able from role to use certificates with validate=true even without [certfiles] section exactly as in https://docs.scylladb.com/stable/operating-scylla/security/gen-cqlsh-file.html

this can be achieved by generating self signed certs in a better way and with needed metadata of node hostnames and IPs