[v2] Non-kube Listener and Connector host validation is too restrictive

[ted-ross]

Describe the bug
When using non-kube sites (via bootstrap), the host fields in Listeners and Connectors must be IP addresses in order to be validated. Symbolic hosts like "localhost" are not valid.

How To Reproduce
Steps to reproduce the behavior:
Create a Listener or Connector using host: localhost and watch it fail.

Expected behavior
Any valid host should be permitted.

Environment details

• Skupper CLI: head of the v2 branch
• Skupper Operator (if applicable): N/A
• Platform: Podman on Fedora

Additional context
None