dex/TEST_MAPPING: referenced non-test modules

TreeHugger can only dereference test modules from test mapping.
This change fixes this particular TEST_MAPPING file to target
FrameworksServicesTest for package com.android.server.pm.dex

Bug: 117497435
Test: atest local run & TreeHugger run, verify the right tests runs.
Change-Id: If8731275b492c7788329de08ac09a9f6437de54a