certificate_statuses endpoint is slow when only querying CSRs

The current method for querying CSRs from puppetserver is to use /puppet-ca/v1/certificate_statuses/ignored?state=requested. Unfortunately, this walks all of the signed certificates instead of just the CSRs, resulting in long query times. We have seen query times of over 2 minutes on this endpoint and they are called often when using the console. This causes long page load times as well as timeouts.

One possible solution that was discussed is to only walk the CSR dir when state=requested https://github.com/puppetlabs/puppetserver/blob/6.x/src/clj/puppetlabs/puppetserver/certificate_authority.clj#L1562-L1563

Outcomes

• Querying CSRs in a specific state should be faster (don't gather data we don't need).