Redirection cookie handling tests for issue #2671

[Zerkath]

Tests for #2671 which are now failing with the following output:

- should pass cookies during redirections *** FAILED *** (13 milliseconds)
  Vector() did not contain element "session" (in Checkpoint) at FollowRedirectsBackendTest.scala:90
  Vector() did not contain element "session" (in Checkpoint) at FollowRedirectsBackendTest.scala:90
  Vector() did not contain element "session" (in Checkpoint) at FollowRedirectsBackendTest.scala:90
  Vector() did not contain element "session" (in Checkpoint) at FollowRedirectsBackendTest.scala:90
  Vector() did not contain element "session" (in Checkpoint) at FollowRedirectsBackendTest.scala:90
  Vector(session=final) did not equal List(0-fuzz=, 1-fuzz=, 2-fuzz=, 3-fuzz=, 4-fuzz=, session=final) (in Checkpoint) 

at FollowRedirectsBackendTest.scala:118 (FollowRedirectsBackendTest.scala:119)

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