token: Refactor token validation decorator.
token: Refactor token validation decorator.

Change-Id: I7d26ba2c67abd047bc439725f3b9407e4becade1

joyxu/kernelci-backend,joyxu/kernelci-backend,kernelci/kernelci-backend,joyxu/kernelci-backend,kernelci/kernelci-backend