Add public keyword to methods

[MAILPOET-2413]

lib/Config/PersonalDataErasers.php

@@ -7,11 +7,11 @@ use MailPoet\WP\Functions as WPFunctions;
 
 class PersonalDataErasers {
 
-  function init() {
+  public function init() {
     WPFunctions::get()->addFilter('wp_privacy_personal_data_erasers', [$this, 'registerSubscriberEraser']);
   }
 
-  function registerSubscriberEraser($erasers) {
+  public function registerSubscriberEraser($erasers) {
     $erasers['mailpet-subscriber'] = [
       'eraser_friendly_name' => WPFunctions::get()->__('MailPoet Subscribers', 'mailpoet'),
       'callback' => [new SubscriberPersonalDataEraser(), 'erase'],