Use i18n directive for email template

issue10328
review321021003

email.html

@@ -1,12 +1,14 @@
 <!DOCTYPE html>
-<html xmlns:py="http://genshi.edgewall.org/">
+<html xmlns:py="http://genshi.edgewall.org/" xmlns:i18n="http://genshi.edgewall.org/i18n">
     <head>
         <title>Gift Card</title>
     </head>
     <body>
         <py:for each="gift_card in records">
         <div style="display: block; text-align: center">
-            <h1>You received a gift card of ${format_currency(gift_card.value, None, gift_card.currency)} for ${gift_card.company.rec_name}.</h1>
+            <h1 i18n:msg="value,company">
+                You received a gift card of ${format_currency(gift_card.value, None, gift_card.currency)} for ${gift_card.company.rec_name}.
+            </h1>
             <h2>Here is your code:</h2>
             <div style="padding: 1em; font-size: 2em;
                         width: max-content; margin-left: auto; margin-right: auto;