Fix broken link to jaspan article

Closes gh-14358

docs/modules/ROOT/pages/servlet/authentication/rememberme.adoc

@@ -52,9 +52,9 @@ If you have more than one in your application context, you need to specify which
 
 [[remember-me-persistent-token]]
 == Persistent Token Approach
-This approach is based on the article https://web.archive.org/web/20180819014446/http://jaspan.com/improved_persistent_login_cookie_best_practice[http://jaspan.com/improved_persistent_login_cookie_best_practice] with some minor modifications  footnote:[Essentially, the username is not included in the cookie, to prevent exposing a valid login name unecessarily.
+This approach is based on the article https://web.archive.org/web/20180819014446/http://jaspan.com/improved_persistent_login_cookie_best_practice[Improved Persistent Login Cookie Best Practice] with some minor modifications  footnote:[Essentially, the username is not included in the cookie, to prevent exposing a valid login name unecessarily.
 There is a discussion on this in the comments section of this article.].
-To use the this approach with namespace configuration, you would supply a datasource reference:
+To use this approach with namespace configuration, you would supply a datasource reference:
 
 [source,xml]
 ----

web/src/main/java/org/springframework/security/web/authentication/rememberme/PersistentTokenBasedRememberMeServices.java

@@ -32,8 +32,8 @@ import org.springframework.security.web.authentication.RememberMeServices;
 import org.springframework.util.Assert;
 
 /**
- * {@link RememberMeServices} implementation based on Barry Jaspan's
- * <a href="http://jaspan.com/improved_persistent_login_cookie_best_practice">Improved
+ * {@link RememberMeServices} implementation based on Barry Jaspan's <a href=
+ * "https://web.archive.org/web/20180819014446/http://jaspan.com/improved_persistent_login_cookie_best_practice">Improved
  * Persistent Login Cookie Best Practice</a>.
  *
  * There is a slight modification to the described approach, in that the username is not