feat: add trailer tags to rss if trailer episodes are present

                $item->addChild('season', (string) $episode->season_number, $itunesNamespace);

            $item->addChild('episodeType', $episode->type, $itunesNamespace);

            // If episode is of type trailer, add podcast:trailer tag on channel level

            if ($episode->type == 'trailer') {

                $trailer = $channel->addChild('trailer', $episode->title, $podcastNamespace);

                $trailer->addAttribute('pubdate', $episode->published_at->format(DATE_RFC2822));

                $trailer->addAttribute(

                    'url',

                    $episode->audio_url . ($enclosureParams === '' ? '' : '?' . $enclosureParams),

                );

                $trailer->addAttribute('length', (string) $episode->audio->file_size);

                $trailer->addAttribute('type', $episode->audio->file_mimetype);

                if ($episode->season_number !== null) {

                    $trailer->addAttribute('season', (string) $episode->season_number);

                }

            }

            // add podcast namespace tags for season and episode

            $episode->season_number &&

                $item->addChild('season', (string) $episode->season_number, $podcastNamespace);