[JENKINS-61738][2] Session hijacking protection hardening (#4615)

* [JENKINS-61738] Session hijacking protection hardening

* Workaround bad test

* Better approach in terms of test

* Get rid of small whitespace

* Update core/src/main/java/hudson/WebAppMain.java

Co-Authored-By: Jeff Thompson <37345299+jeffret-b@users.noreply.github.com>

* Update war/src/main/webapp/WEB-INF/web.xml

Co-Authored-By: Jeff Thompson <37345299+jeffret-b@users.noreply.github.com>

* Use release companion PR

Co-authored-by: Jeff Thompson <37345299+jeffret-b@users.noreply.github.com>