Revert^2 "Make adbconnection start automatically for debuggable apps (on target)"

This reverts commit b2926c0c.

We were trying to start with adbconnection but that was not always
available on devices. This could cause tests to fail.

Bug: 109505014
Reason for revert: Fixed issue causing target tests to sometimes fail.
Test: ./test.py --target

Change-Id: I0bb9cd2dce87145a8a9c372e2f015e36a3276369