Add the 50k monthly plan on frontend

Author: AchoArnold

web/pages/billing/index.vue

@@ -424,6 +424,18 @@ export default Vue.extend({
           messagesPerMonth: 20000,
           price: 350,
         },
+        {
+          name: '50k - Monthly',
+          id: '50k-monthly',
+          messagesPerMonth: 50000,
+          price: 89,
+        },
+        {
+          name: '50k - Yearly',
+          id: '50k-yearly',
+          messagesPerMonth: 50000,
+          price: 890,
+        },
         {
           name: '100k - Monthly',
           id: '100k-monthly',