Blockbase + children: Add footer credits that wordpress.com will recognise (#4142)

mayland-blocks/block-template-parts/footer.html

@@ -18,4 +18,8 @@
 <!-- wp:navigation-link {"label":"Contact","url":"#"} /-->
 <!-- /wp:navigation --></div>
 <!-- /wp:column --></div>
-<!-- /wp:columns -->
+<!-- /wp:columns -->
+
+<!-- wp:paragraph {"align":"center"} -->
+<p class="has-text-align-center">Proudly Powered by <a href="https://wordpress.org" rel="nofollow">WordPress</a></p>
+<!-- /wp:paragraph -->

quadrat/block-template-parts/footer.html

@@ -2,8 +2,8 @@
 <div class="wp-block-group site-footer" style="padding-top:150px;padding-bottom: 150px">
 
 <!-- wp:paragraph {"align":"center"} -->
-<p class="has-text-align-center">Powered by WordPress</p>
+<p class="has-text-align-center">Proudly Powered by <a href="https://wordpress.org" rel="nofollow">WordPress</a></p>
 <!-- /wp:paragraph -->
 
 </div>
-<!-- /wp:group -->
+<!-- /wp:group -->

seedlet-blocks/block-template-parts/footer.html

@@ -10,7 +10,7 @@
 <!-- /wp:paragraph -->
 
 <!-- wp:paragraph {"align":"left","fontSize":"small"} -->
-<p class="has-text-align-left has-small-font-size">Proudly powered by <a href="https://wordpress.org">WordPress</a></p>
+<p class="has-text-align-left has-small-font-size">Proudly Powered by <a href="https://wordpress.org" rel="nofollow">WordPress</a></p>
 <!-- /wp:paragraph --></div>
 <!-- /wp:group -->