Revert "Make sure that the LockTaskUtilityActivityIfWhitelisted was started."

Original change: https://android-review.googlesource.com/c/platform/cts/+/1347425

This reverts commit 216ed1555b5f60ad048f503f985722fbf448a7f8.

Reason for revert: the added testLockTaskIsActive check does not
work as intended since starting a new instrumentation test case
kills the test package, which also kills the lock task activity
which belongs to the same package.

Bug: 159605606
Bug: 146006729
Test: builds
Merged-In: I2c346f0153f214b698f0780683198918cd14c3ee
Change-Id: I2c346f0153f214b698f0780683198918cd14c3ee
(cherry picked from commit bc65384dc006a38aaeeaf1c276dce2aa9eaea5fb)
2 files changed