update year

ruoyi-admin/src/main/resources/templates/register.html

@@ -64,7 +64,7 @@
         </div>
         <div class="signup-footer">
             <div class="pull-left">
-                &copy; 2019 All Rights Reserved. RuoYi <br>
+                &copy; 2018-2021 All Rights Reserved. RuoYi <br>
             </div>
         </div>
     </div>