(REPLATS-188) Preload Puppet certs

[Iristyle]

Depends on https://github.com/puppetlabs/puppetserver/pull/2516 https://github.com/puppetlabs/puppetserver/pull/2518 and shipping an updated container image (done in https://github.com/puppetlabs/puppetserver/runs/2232094590?check_suite_focus=true)

• Create a docker-compose.fixtures.yml to follow the same basic separation that has been done in repos like pupperware-commercial

• Boots puppetserver more quickly by skipping CA file generation. Opt-in by setting PRELOAD_CERTS=1 environment variable

• Requires minimal volume setup so that the docker_compose_up helper has places to copy certificates during startup

• Now that the ca and certs directory are separate in puppetserver, leverages the new CERT_DESTDIR setting to make sure that certs are copied into the appropriate locations within puppetserver

• Adds a new optional CERT_SRCDIR setting to decide where to retrieve certs for a given service from. Typically it defaults to a directory with the same name as the service, but can be overridden (as is the case for puppetserver oss). This prevents having to change service name (which is embedded in many of the spec helpers as 'puppet')

• Temporarily switches to using 'edge' container for puppetserver (currently based on 7.1.0) as it contains an entrypoint fix needed to properly load the certs

[Iristyle]

Azure probs are perf related as they have been in the past