Fix login -> move to bootstrap5

uncloud_pay/templates/uncloud_pay/register_stripe.html

@@ -13,12 +13,15 @@
           By submitting I authorise to send instructions to
           the financial institution that issued my card to take
           payments from my card account in accordance with the
-        terms of my agreement with you.
+          terms of my agreement with you.
         </p>
 
         <span id="message"></span>
+
         <div id="card-element"></div>
+        <div id="card-errors" role="alert"></div>
         <button type='button' id="card-button">Save</button>
+
         <div id="ungleichmessage">The card will be registered with stripe.</div>
 
         <div id="goback" style="display: none;">
@@ -30,8 +33,8 @@
     <!-- Enable Stripe from UI elements - standard code -->
     <script>
       var stripe = Stripe('{{ stripe_pk }}');
-
       var elements = stripe.elements();
+
       var cardElement = elements.create('card');
       cardElement.mount('#card-element');