Add VTS test to check grants are deleted upon grantee app uninstall.

The "atest" command below fails for this new test when run on a revision
without the fix in aosp/3527935, which is what we expect.

Bug: 372415590
Test: atest keystore2_client_tests
Change-Id: I7bb265e154748b4a01a8334370efb44bb05ea339
1 file changed