Split slower tests to a separate test target am: 7e5b405961 am: 2cb22712e2 am: 3dbf977064 am: 614f4bb4d2

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2037624

Change-Id: I010848fa3a40df9b06936947e9762e9c9748e380