Fix isolated spec test

Author: hgreebe

cookbooks/aws-parallelcluster-environment/spec/unit/recipes/isolated_install_spec.rb

@@ -26,7 +26,7 @@
 
       it 'has the correct content' do
         is_expected.to render_file("#{node['cluster']['scripts_dir']}/patch-iso-instance.sh")
-          .with_content("USERS=(root #{node['cluster']['cluster_admin_user']} #{node['cluster']['cluster_user']})")
+          .with_content("source /etc/profile.d/aws-cli-default-config.sh")
       end
     end
   end

cookbooks/aws-parallelcluster-environment/test/controls/isolated_spec.rb

@@ -17,6 +17,5 @@
     its('owner') { should cmp 'root' }
     its('group') { should cmp 'root' }
     its('mode') { should cmp '0744' }
-    its('content') { should match /USERS=\(root #{node['cluster']['cluster_admin_user']} #{node['cluster']['cluster_user']}\)/ }
   end
 end