payments: Add an amount field to the stripe payment form.

r2/r2/public/static/css/reddit.less

@@ -6638,7 +6638,7 @@ body.gold .buttons li.comment-save-button { display: inline; }
     white-space:nowrap;
     font-size:smaller;
 }
-
+#stripe-payment .credit-card-amount { text-align: left; }
 #stripe-payment th label { display:inline; }
 #stripe-payment td input {
     font-size:small;

r2/r2/templates/goldpayment.html

@@ -156,6 +156,10 @@
       <div>${_('Stripe is PCI compliant and your credit card information is sent directly to them.')}</div>
     </div>
     <table class="credit-card-input">
+      <tr>
+        <th><label>${_('amount')}</label></th>
+        <th class="credit-card-amount">${thing.price}</th>
+      </tr>
       <tr>
         <th><label>${_('name')}</label></th>
         <td><input type="text" autocomplete="off" class="card-name"></td>