Support for SoundCloud

Apparently, I am not allowed to fork things as I reached my "limit". Unsure what that means but here is what I modified:

<?php

namespace Drupal\social_link_field\Plugin\SocialLinkField\Platform;

use Drupal\social_link_field\PlatformBase;

/**
 * Provides 'soundcloud' platform.
 *
 * @SocialLinkFieldPlatform(
 *   id = "soundcloud",
 *   name = @Translation("SoundCloud"),
 *   icon = "fa-soundcloud",
 *   urlPrefix = "https://soundcloud.com/",
 * )
 */
class SoundCloud extends PlatformBase {}