Switch to new NetworkTimeHelper impl

Switch default from a NetworkTimeHelper impl that explicitly syncs NTP
to get a network time to one that retrieves the latest network time from
the time detector.

Behavior can be observed using:
adb shell dumpsys location -a
  - look for the NetworkTimeHelper info

Bug: 222295093
Test: build / boot / inspect
Change-Id: I40bb317971ca42e2739edd5c7351b32f0f329440