Replace Ubuntu 14.04 tests with 18.04

Author: ekohl

spec/classes/apache_spec.rb

@@ -241,8 +241,8 @@
       it { is_expected.to contain_exec('/usr/sbin/a2dismod prefork') }
     end
 
-    context 'on Ubuntu 14.04' do
-      include_examples 'Ubuntu 14.04'
+    context 'on Ubuntu 18.04' do
+      include_examples 'Ubuntu 18.04'
 
       it {
         is_expected.to contain_file('/var/www/html').with(

spec/spec_helper_local.rb

@@ -41,18 +41,8 @@
   let(:facts) { on_supported_os['debian-8-x86_64'] }
 end
 
-shared_context 'Ubuntu 14.04' do
-  let :facts do
-    {
-      id: 'root',
-      kernel: 'Linux',
-      osfamily: 'Debian',
-      operatingsystem: 'Ubuntu',
-      operatingsystemrelease: '14.04',
-      lsbdistrelease: '14.04',
-      path: '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin',
-    }
-  end
+shared_context 'Ubuntu 18.04' do
+  let(:facts) { on_supported_os['ubuntu-18.04-x86_64'] }
 end
 
 shared_context 'RedHat 6' do