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
Change-Id: I269962a30f224fd434a1915c9b1bf264f20b780c
3 files changed
tree: 8ed7c5c95b026a53f1b748279957fecb5078a511
  1. tests/