Removing exclamation as it is only for shadowi

Signed-off-by: imjoseangel <josea.munoz@gmail.com>

Author: imjoseangel

controls/os_spec.rb

@@ -104,7 +104,7 @@
   title 'Check passwords hashes in /etc/passwd'
   desc 'Check periodically that /etc/passwd does not contain passwords'
   describe passwd do
-    its('passwords') { should be_in ['x', '*', '!'] }
+    its('passwords') { should be_in ['x', '*'] }
   end
 end