theme: default: update link to git repo

Author: PeterCxy

theme/default/copyright.hbs

@@ -1,5 +1,5 @@
 <section class="copyright">
     Copyright © {{ cur_year }} {{ blog.title }}<br />
-    Powered by <a href="https://github.com/PeterCxy/paprika" target="_blank">paprika</a><br />
+    Powered by <a href="https://cgit.typeblog.net/paprika" target="_blank">paprika</a><br />
     Hosted on <a href="https://workers.cloudflare.com/" target="_blank">Cloudflare Workers</a>
-</section>
+</section>