(profile::core::puppet_master) install oauth gem in puppet agent env

puppet6 aio bundles the oauth gem but it is not bundled with puppet7
aio.  Most of the native types in `theforeman/foreman` require this gem
to be present.

See: theforeman/puppet-foreman#1077

site/profile/manifests/core/puppet_master.pp

@@ -194,4 +194,9 @@
 
  # for bmc management
  ensure_packages(['ipmitool'])
+
+ package { 'oauth':
+ ensure => installed,
+ provider => 'puppet_gem',
+ }
 }

spec/hosts/roles/foreman_spec.rb

@@ -164,6 +164,8 @@
  ],
  )
  end
+
+ it { is_expected.to contain_package('oauth').with_provider('puppet_gem') }
 end
 
 role = 'foreman'