Clean up services created after running test

Services created during new tests weren't properly cleaned up after tests. It caused slowdown of subsequent tests as described in b/244486404.
This change kills/terminates services after test with apex services.

To provide some context, original change is at https://android-review.googlesource.com/q/topic:vapex_stop_service. The issue was discovered by android test monitor and filed as a P0 bug.

Bug: 244486404
Change-Id: Ie64e0eb1686e94ef543a457ea49d1d7aeab38c97