Replace check_if_subscriber_in_array()

This is no longer needed, as we query the API by `email_address`, so inspecting the response’s `total_subscribers` is sufficient.

Author: n7studios

src/ConvertKit_API.php

@@ -438,15 +438,13 @@ public function get_subscriber_id(string $email_address)
             return false;
         }
 
-        $subscriber_id = $this::check_if_subscriber_in_array($email_address, $subscribers->subscribers);
-
-        if ($subscriber_id) {
-            return $subscriber_id;
+        if ($subscribers->total_subscribers === 0) {
+            $this->create_log('No subscribers');
+            return false;
         }
 
-        $this->create_log('Subscriber not found');
-
-        return false;
+        // Return the subscriber's ID.
+        return $subscribers->subscribers[0]->id;
     }
 
 
@@ -761,26 +759,4 @@ public function make_request(string $endpoint, string $method, array $args = [])
         $this->create_log('Failed to finish request.');
         return false;
     }
-
-
-    /**
-     * Looks for subscriber with email in array
-     *
-     * @param string $email_address Email Address.
-     * @param array  $subscribers   Subscribers.
-     *
-     * @return false|integer  false if not found, else subscriber object
-     */
-    private function check_if_subscriber_in_array(string $email_address, array $subscribers)
-    {
-        foreach ($subscribers as $subscriber) {
-            if ($subscriber->email_address === $email_address) {
-                $this->create_log('Subscriber found!');
-                return $subscriber->id;
-            }
-        }
-
-        $this->create_log('Subscriber not found on current page.');
-        return false;
-    }
 }