Fix demo: use gh-pages branch

Author: melvincarvalho

demo.html

@@ -183,7 +183,7 @@ <h3>Connect to a Git Repo</h3>
     </div>
     <div class="field">
       <label>Branch</label>
-      <input type="text" id="branch" value="main" placeholder="main">
+      <input type="text" id="branch" value="gh-pages" placeholder="main">
     </div>
     <div class="field">
       <label>Nostr Relay</label>