Change regex to allow multiple spaces. (#35)

HardeningFramework-DCO-1.1-Signed-off-by: Tim Stoop <github@timstoop.nl> (github: timstoop)

controls/5_4_user_accounts_and_environments.rb

@@ -199,6 +199,6 @@
   tag level: 1
 
   describe file('/etc/pam.d/su') do
-    its(:content) { should match(/^auth required pam_wheel.so use_uid$/) }
+    its(:content) { should match(/^auth\s+required\s+pam_wheel.so use_uid$/) }
   end
 end