drop parallel_tests + bump puppetlabs_spec_helper
drop parallel_tests + bump puppetlabs_spec_helper

latest puppetlabs_spec_helper has a dependency for parallel_tests, so we
don't need to specify it.

voxpupuli/modulesync_config,dhoppe/modulesync_config,dhoppe/modulesync_config,dhoppe/modulesync_config,puppet-community/modulesync_config,voxpupuli/modulesync_config,voxpupuli/modulesync_config,voxpupuli/modulesync_config,dhoppe/modulesync_config