Add sponsor banner to other layout too.

Author: geerlingguy

_layouts/card.html

@@ -16,6 +16,7 @@
     <!-- HEADER -->
     <div id="header_wrap" class="outer">
         <header class="inner">
+          <a id="sponsor_banner" href="https://github.com/sponsors/geerlingguy">Sponsor</a>
           <a id="forkme_banner" href="https://github.com/geerlingguy/raspberry-pi-pcie-devices">View on GitHub</a>
 
           <h2 id="project_title"><a href="/">{{ site.title }}</a></h2>