fix: deprecated notice

Author: girishpanchal30

includes/abstract/feedzy-rss-feeds-admin-abstract.php

@@ -858,7 +858,7 @@ private function init_feed( $feed_url, $cache, $sc, $allow_https = FEEDZY_ALLOW_
 		require_once ABSPATH . WPINC . '/class-wp-feed-cache-transient.php';
 		require_once ABSPATH . WPINC . '/class-wp-simplepie-file.php';
 
-		$feed->get_registry( 'WP_SimplePie_File' );
+		$feed->get_registry()->register( SimplePie\File::class, 'WP_SimplePie_File' );
 		$default_agent = $this->get_default_user_agent( $feed_url );
 		$feed->set_useragent( apply_filters( 'http_headers_useragent', $default_agent ) );
 		if ( false === apply_filters( 'feedzy_disable_db_cache', false, $feed_url ) ) {