use an existing certificate for services if available

[ddollar]

if a certificate already exists that matches all of the domains for a service, use it instead of creating a new one

[ndbroadbent]

I'm still seeing a request for a duplicate certificate in AWS Certificate Manager. My rack version is: 20180524143822.

My convox.yml is like this:

services:
  web:
    domain:
      - subdomain.example.com

The first request sent verification emails to postmaster@subdomain.example.com, administrator@subdomain.example.com, etc.

On my next deploy, it created another certificate for the same domain, with a status of Pending validation. But it sent out the verification emails to different addresses: postmaster@example.com, administrator@example.com, etc.