Prevent wtf crash test app

TcpSocketTrackerTest will need to verify some unexpected cases
work as intended or not. In these cases, module may log wtf log.
However, AM will crash application if wtf log is found in eng
build. Test will fail due to test app crashed. Thus, set the
wtf handler in test to Log.e to prevent it.

Bug: 146909385
Test: atest NetworkStackTests:\
com.android.networkstack.netlink.TcpSocketTrackerTest#testPollSocketsInfo_BadFormat
in eng build
Test: atest NetworkStackNextTests:\
com.android.networkstack.netlink.TcpSocketTrackerTest#testPollSocketsInfo_BadFormat
in eng build

Change-Id: I12f4125496f58fc8a47b124b4a47de6c2d0a386b