Discourage Samples apps
Discourage Samples apps

No change to logic, only adds a comment.

The new recommended policy is to add "testapps" under
<module>/integration-tests/testapp (as per http://aosp/774484).

This adds a comment explaining the new policy.

Test: N/A
Change-Id: I9f8205928a18b20c7e603af89a4a8cac0772ffef

AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,androidx/androidx