Move the NetworkStack tests to unit/ to add an integration test.

Test: m
Bug: 133389827
(cherry pick from aosp/960932)
Merged-In: I7aeab47b31429b1f9a42f9b170aeba238c133950
Change-Id: Ie455b7a6a950cb5e34841efc3738c11fe1fd12f0
21 files changed