Do not allow users at server limit to clone servers

What does this MR do and why?

Do not allow users to clone server if the server limit has been reached.

Screenshots or screen recordings

How to set up and validate locally

Click clone server

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• Have you checked this doesn't interfere/conflict/duplicate someone elses work?
• Have you fully tested your changes?
• Have you resolved any lint issues?
• Have you assigned a reviewer?
• Have you applied correct labels?