ENGCOM-2549: Set proper text-aligh for the <th> element of the Subtotal column in the Creditmemo email #17153

 - Merge Pull Request #17153 from TomashKhamlai/magento2:fix-creditmemo-email-less
 - Merged commits:
   1. e98ffc7

Author: magento-engcom-team

app/design/frontend/Magento/blank/Magento_Sales/web/css/source/_email.less

@@ -203,7 +203,8 @@
         text-align: center;
     }
 
-    .item-price {
+    .item-price,
+    .item-subtotal {
         text-align: right;
     }
 

app/design/frontend/Magento/luma/Magento_Sales/web/css/source/_email.less

@@ -207,7 +207,8 @@
         text-align: center;
     }
 
-    .item-price {
+    .item-price,
+    .item-subtotal {
         text-align: right;
     }