Update/arbutus wip (#5053)

* Arbutus: Add theme screenshot.

* Arbutus: Remove specific links from the footer social menu.

* Arbutus: Simplify the footer nav.

* Arbutus: Update screenshot after updating header layout.

arbutus/block-template-parts/footer.html

@@ -8,12 +8,6 @@
 <p class="has-small-font-size"><meta charset="utf-8"><strong>Proudly Powered by <a rel="nofollow" href="https://wordpress.org">WordPress</a></strong></p>
 <!-- /wp:paragraph -->
 
-<!-- wp:social-links {"iconColor":"primary","iconColorValue":"#343e47","size":"has-small-icon-size","className":"is-style-logos-only"} -->
-<ul class="wp-block-social-links has-small-icon-size has-icon-color is-style-logos-only"><!-- wp:social-link {"url":"#","service":"twitter"} /-->
-
-<!-- wp:social-link {"url":"#","service":"instagram"} /-->
-
-<!-- wp:social-link {"url":"#","service":"tumblr"} /--></ul>
-<!-- /wp:social-links --></div>
+<!-- wp:navigation {"itemsJustification":"center","overlayMenu":"never","__unstableSocialLinks":"social"} /--></div>
 <!-- /wp:group --></div>
 <!-- /wp:group -->