(maint) acceptance tests: always use released pdb module

acceptance/helper.rb

@@ -441,15 +441,7 @@ def get_package_version(host, version = nil)
  end
 
  def install_puppetdb_module(hosts, puppet_platform)
- if test_config[:install_mode] == :upgrade_oldest
- # Use custom branch of puppetlabs-postgres for puppet 6 agents with gpg keys updated for last module release that was puppet 6 compatible
- on(hosts, 'curl -L https://github.com/puppetlabs/puppetlabs-postgresql/archive/refs/heads/backport-gpg-key.tar.gz --output /tmp/puppetlabs-postgresql')
- on(hosts, 'puppet module install /tmp/puppetlabs-postgresql')
- on(hosts, 'puppet module install puppetlabs-puppetdb --version 7.13.0')
- else
- # While we sort out a new puppetlabs-puppetdb module release, point to a branch that allows us to take the latest puppetlabs-postgresql module
- on(hosts, 'puppet module install puppetlabs-puppetdb')
- end
+ on(hosts, 'puppet module install puppetlabs-puppetdb')
  end
 
  def install_puppetdb(host, version=nil)