Add tests related to V2 token issued_at time changing

There was no test that showed that when a V2 token is used in a V3
context its "issued_at" time changes. This affects validating a V2
token using V3 and also revoking a V2 token. The tests show the
current incorrect behavior.

Partial-Bug: #1348820

Change-Id: I2a3443847b2699384413933ae164fdc183aa110f
(cherry picked from commit 556fb860311675fc437585651e4602b2908451eb)