Footer: Add link to WordPress Swag store

Fixes #318.

Author: coffee2code

mu-plugins/blocks/global-header-footer/footer.php

@@ -33,6 +33,7 @@
 			<!-- wp:navigation-link {"label":"<?php echo esc_html_x( 'News', 'Menu item title', 'wporg' ); ?>","url":"https://wordpress.org/news/","kind":"custom","isTopLevelLink":true} /-->
 			<!-- wp:navigation-link {"label":"<?php echo esc_html_x( 'Hosting', 'Menu item title', 'wporg' ); ?>","url":"https://wordpress.org/hosting/","kind":"custom","isTopLevelLink":true} /-->
 			<!-- wp:navigation-link {"label":"<?php echo esc_html_x( 'Donate', 'Menu item title', 'wporg' ); ?>","url":"https://wordpressfoundation.org/donate/","kind":"custom","isTopLevelLink":true} /-->
+			<!-- wp:navigation-link {"label":"<?php echo esc_html_x( 'Swag', 'Menu item title', 'wporg' ); ?>","url":"https://mercantile.wordpress.org/","kind":"custom","isTopLevelLink":true} /-->
 		<!-- /wp:navigation -->
 
 		<!-- wp:navigation {"orientation":"vertical","className":"global-footer__navigation-information","overlayMenu":"never"} -->