Force the realm to be "Test Realm" when responding to challenges, since all credentials are created in that realm.
Force the realm to be "Test Realm" when responding to challenges, since all credentials are created in that realm.

git-svn-id: 0c33e958600270102f91bf5868e396345dde476c@7787 e27351fd-9f3e-4f54-a53b-843176b1656c

red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver