Add: register button on manage page

web/src/component/Manage.js

@@ -9,6 +9,7 @@ function Manage(props) {
       <h2>Manage</h2>
       <p>Hi, {props.user.username}</p>
       {props.user.role === 0 && (
+        <div>
           <button
             onClick={() => {
               navigate("/manage/login");
@@ -16,6 +17,14 @@ function Manage(props) {
           >
             Login
           </button>
+          <button
+            onClick={() => {
+              navigate("/manage/register");
+            }}
+          >
+            Register
+          </button>
+        </div>
       )}
       {props.user.role !== 0 && (
         <div className="horizontal">