getPaginateFollowing pagination fix (#792)

The $endCursor inside getPaginateFollowing() line no: 1460 was empty changed to $nextPage

Author: jeybin

src/InstagramScraper/Instagram.php

@@ -1457,7 +1457,7 @@ public function getPaginateFollowing($accountId, $count = 20, $pageSize = 20, $d
 
         $index = 0;
         $accounts = [];
-        $endCursor = '';
+        $endCursor = $nextPage;
         $lastPagingInfo = [];
 
         if ($count < $pageSize) {