Add rel="me" Mastodon verification (#1346)

Author: Shrinks99

source/_includes/footer.liquid

@@ -15,6 +15,7 @@
       </div>
       <div class="sl-l-grid__column sl-l-large-grid__column--auto-size sl-l-large-grid--justify-right sl-c-footer-link-grid">
         <a
+            rel="me"
             class="sl-c-button sl-c-button--icon sl-c-button--icon-text"
             href="https://front-end.social/@sass">
           {%- render 'icons/mastodon' -%}