Add rubocop spacing rules

We were following these rules in most places; we just didn't define them
anywhere.

app/views/devise/confirmations/new.html.erb

@@ -13,7 +13,7 @@
           <p><%= f.password_field :password_confirmation %></p>
       <% end %>
 
-      <%= hidden_field_tag :confirmation_token,@confirmation_token %>
+      <%= hidden_field_tag :confirmation_token, @confirmation_token %>
 
       <div class="small-12 medium-6 small-centered">
         <%= f.submit(t("devise_views.confirmations.new.submit"), class: "button expanded") %>