Related to #6220 The `AbstractRememberMeServices` attempts to [use the setHttpOnly method only if that method is available in javax.servlet.http.Cookie](https://github.com/spring-projects/spring-security/blob/master/web/src/main/java/org/springframework/security/web/authentication/rememberme/AbstractRememberMeServices.java#L97). Since Spring Framework 5.0 has a Servlet Spec baseline of 3.1, this check is no longer necessary. We should always use the setHttpOnly method and remove [any corresponding Servlet 2.5 or 3.0 tests](https://github.com/spring-projects/spring-security/blob/master/web/src/test/java/org/springframework/security/web/authentication/rememberme/AbstractRememberMeServicesServlet3Tests.java).