feat: add TestFlight-related questions

thanks to @JanGross

src/index.liquid

@@ -92,6 +92,11 @@ layout: layouts/base
         <p><a href="https://github.com/glenjamin/node-fib/#is-it-any-good" target="_blank" rel="noopener noreferer">Yes.</a></p>
     </div>
 
+    <div class="c-faq__section">
+        <h5>Is there a TestFlight program?</h5>
+        <p>A frequently updated development build is available. <a href="https://testflight.apple.com/join/913htqtU" target="_blank" rel="noopener noreferer">Join here.</a></p>
+    </div>
+
     <div class="c-faq__section">
         <p>If your question is not listed here, I'm reachable via email at <a href="mailto:oss@rizaldy.club">oss@rizaldy.club</a> or <a href="https://edgy.social/@rizaldy" target="_blank" rel="noopener noreferer">@rizaldy@edgy.social</a> on Fediverse. You can also use <a href="https://github.com/kepelet/flo/discussions" target="_blank" rel="noopener noreferer">GitHub Discussions</a> for non-private questions.</p>
     </div>