Fix package suffix spec test

[ghoneycutt]

This is related to PR #615

Failures:

  1) sensu package setting version with redhat platform version suffix should contain Package[sensu] with ensure => "0.29.0-1.el7"
     Failure/Error:
       it { should contain_package('sensu').with(
         :ensure => '0.29.0-1.el7'
       ) }

       expected that the catalogue would contain Package[sensu] with ensure set to "0.29.0-1.el7" but it is set to "0.29.0-1.el7.el7"
     # ./spec/classes/sensu_package_spec.rb:53:in `block (5 levels) in <top (required)>'

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369 examples, 1 failure