Hide user password

Override the is_to_s and should_to_s
methods in the puppet property to make
sure it's not shown in outputs.

Closes: #839

Author: tobias-urdin

lib/puppet/type/rabbitmq_user.rb

@@ -46,6 +46,16 @@ def insync?(_is)
     def change_to_s(_current, _desired)
       'password has been changed'
     end
+
+    # rubocop:disable Style/PredicateName
+    def is_to_s(_value)
+      '[old password redacted]'
+    end
+    # rubocop:enable Style/PredicateName
+
+    def should_to_s(_value)
+      '[new password redacted]'
+    end
   end
 
   newproperty(:admin) do