[Feature Request] Replace SSL Cert upon delete of another

[brandoningli]

Is your feature request related to a problem? Please describe.

I'm in the process of migrating from using an SSL cert I uploaded to one Let's Encrypt fetches from within NPM. After creating the new LE cert and deleting the custom one, I now have to manually go in and update the SSL settings on each host to not only use the new cert, but use the other auxiliary settings they were using.

Describe the solution you'd like

When deleting an SSL cert, assuming another is configured, ask if the user would like to migrate to using a different cert. If so, replace the old cert with the new one in the host configs instead of resetting them all to HTTP Only, keeping the other settings like Force SSL along the way.

Describe alternatives you've considered

Additional context