Reduce number of OS combinations for tests

This change reduces the amount of different operating system
combinations that we will use for our unit tests. Previously we were
running tests on both CentOS 7 and RedHat 7 which are pretty much
identical for our modules. Additionally we were testing two versions
of Fedora (21 and 22) and two versions of Debian (7 and 8).

This change leaves the following OS combinations for unit tests:
- CentOS 7
- Fedora 22
- Ubuntu 14.04
- Debian 8

If a change adds any specific operating system requirements, like
actually looking for RedHat specifically, the test should be updated
with a specific case for RedHat rather than globally testing for
RedHat.

Change-Id: Ib9be991897e8707342f984caccb3f75aa26742e2

lib/puppet-openstack_spec_helper/defaults.rb

@@ -9,14 +9,12 @@ module OSDefaults
     [
       { 'operatingsystem'        => 'CentOS',
         'operatingsystemrelease' => [ '7.0' ] },
-      { 'operatingsystem'        => 'RedHat',
-        'operatingsystemrelease' => [ '7.0' ] },
       { 'operatingsystem'        => 'Fedora',
-        'operatingsystemrelease' => [ '21', '22' ] },
+        'operatingsystemrelease' => [ '22' ] },
       { 'operatingsystem'        => 'Ubuntu',
         'operatingsystemrelease' => [ '14.04' ] },
       { 'operatingsystem'        => 'Debian',
-        'operatingsystemrelease' => [ '7', '8' ] }
+        'operatingsystemrelease' => [ '8' ] }
     ]
   end
 end