Fix testResNApi in MultinetworkApiTest

This test can not pass in T-Mobile Network becauseT-Mobile
has configured their network to return a "search page" when
the user looks up a name that doesn't exist.
Enable private DNS strict mode before doing testResNApi

Bug: 144521720
Test: atest MultinetworkApiTest

(cherry picked from commit a0d1ae43bf781fad6f4e06316dde993d4c87c77a)

Change-Id: Id47045503adb0575c5f9e15fbc732c3c62912a9a
3 files changed
tree: 1e4c2ab1d723298e192e2327c2e2b8548d89a22c
  1. tests/