Add Let's Encrypt support to serverless domain offering

This is the 2nd step of Instance / group / project level serverless domains with SSL (&2136 (closed))

Problem to solve

As a developer, in order to get started quickly, I would like to use GitLab Serverless' domain provisioning with a Let's Encrypt certificate.

Intended users

• Delaney (Development Team Lead)
• Sasha (Software Developer)
• Devon (DevOps Engineer)
• Sidney (Systems Administrator)

Further details

Proposal

• we want to go with wildcart certificates. The verification for wildcard certs should be implemented as part of this issue.

The UI on the domain settings page is the following

Permissions and Security

Documentation

Testing

What does success look like, and how can we measure that?

What is the type of buyer?

Core

Links / references