Removes all the deprecated resources for paste
support in keystone which we notified about in Stein.
Keystone doesn't use paste so it doesn't work in Stein
either so we remove it for Train.
Depends-On: https://review.opendev.org/#/c/658546/
Change-Id: Id7dfdf2f5cb9453044d39812b7cbd216b7f3eb50