top button goes to /feature (#514)

Co-authored-by: Austin Parker <[email protected]>

Author: puckpuck

src/featureflagservice/lib/featureflagservice_web/templates/layout/root.html.heex

@@ -18,7 +18,7 @@
             <li><%= link "New feature flag", to: Routes.feature_flag_path(@conn, :new) %></li>
           </ul>
         </nav>
-        <a href="/" class="button">
+        <a href="/feature" class="button">
           Feature Flags
         </a>
       </section>