CtsPermission2TestCases secondary_user

Marks this CTS test module as supporting secondary_user, meaning that
the tests are eligible to be run from a regular Android user other
than the system user (i.e. other than user 0).

Note that 'user' here refers to the concept of users in Android
Multiuser; it is NOT the same as a uid.

Bug: 172080546
Bug: 172074161
Change-Id: Ib8004fee23dbf5a73343dcec8a21a97ce1320b80
Test: atest CtsPermission2TestCases --user-type secondary_user
Merged-In: I256069bc14d4789714a89c972f3f12fb866a4375