docs: update about ports and ssl cert for virtualhost feature

[thotz]

The users need to careful about port and ssl certs while consuming virtual host feature for rgw.

Fixes: #14087

Checklist:

• [ ] Commit Message Formatting: Commit titles and messages follow guidelines in the developer guide.
• [ ] Reviewed the developer guide on Submitting a Pull Request
• [ ] Pending release notes updated with breaking and/or notable changes for the next minor release.
• [ ] Documentation has been updated, if necessary.
• [ ] Unit tests have been added, if necessary.
• [ ] Integration tests have been added, if necessary.