Update copyright year in templates.

tmpl/id_v1_login.tmpl

@@ -42,7 +42,7 @@
                 </form>
             </div>
             <div class="footer">
-                Copyright &copy; Kestrel 2023. Released under the terms of the 4-clause BSD license.
+                Copyright &copy; Kestrel 2024. Released under the terms of the 4-clause BSD license.
             </div>
         </div>
     </body>

tmpl/um_index.tmpl

@@ -71,7 +71,7 @@
                 </form>
             </div>
             <div class="footer">
-                Copyright &copy; Kestrel 2023. Released under the terms of the 4-clause BSD license.
+                Copyright &copy; Kestrel 2024. Released under the terms of the 4-clause BSD license.
             </div>
         </div>
     </body>