Explicitly revoke the permission before verification.

For some reason, permission was being granted to the test
app while running the test. So, explicitly revoke the
permission before running the verification.

Bug: 233710271
Test: atest ./hostsidetests/blobstore/src/com/android/cts/host/blob/BlobStoreMultiUserTest.java
Change-Id: I68072e49b9f0e97b67438151e9744f87dd77c072
2 files changed