Initialize NPS poll only once

[MAILPOET-1688]

assets/js/src/nps_poll.jsx

@@ -25,26 +25,10 @@ function displayPoll() {
     && window.satismeter
     && window.mailpoet_installed_at_isoFormat
   ) {
-    // New users poll
+    const newUsersPollId = '6L479eVPXk7pBn6S';
+    const oldUsersPollId = 'k0aJAsQAWI2ERyGv';
     window.satismeter({
-      writeKey: '6L479eVPXk7pBn6S',
+      writeKey: window.mailpoet_is_new_user ? newUsersPollId : oldUsersPollId,
-      userId: window.mailpoet_current_wp_user.ID + window.mailpoet_site_url,
-      traits: {
-        name: window.mailpoet_current_wp_user.user_nicename,
-        email: window.mailpoet_current_wp_user.user_email,
-        createdAt: window.mailpoet_installed_at_isoFormat,
-      },
-      events: {
-        submit: (response) => {
-          if (response.rating >= 9 && response.completed) {
-            showReviewRequestModal();
-          }
-        },
-      },
-    });
-    // Old users poll
-    window.satismeter({
-      writeKey: 'k0aJAsQAWI2ERyGv',
       userId: window.mailpoet_current_wp_user.ID + window.mailpoet_site_url,
       traits: {
         name: window.mailpoet_current_wp_user.user_nicename,