(WIP)(maint) Run CI with pre-generated certs

[Iristyle]

Depends on:

• [x] Merging #179 to load pre-generated certs

• [ ] Refactoring puppetserver container to have some locations as pe-puppetserver

• This will slightly speed up the puppetdb wait time

• Note that this requires moving PGDATA from /var/lib/postgresql/data to /var/lib/postgresql/data/pgdata. This is necessary because PGDATA must be empty when the container first starts to run initdb. With certs copied into a sub-directory of PGDATA, startup fails with a message like:

  initdb: directory "/var/lib/postgresql/data" exists but is not empty

[Iristyle]

Took care of this in #241 finally