Migrate cts/tests/tests/net to androidx.test

See go/jetpack-test-android-migration

This is the internal version of aosp/915793

Exempt-From-Owner-Approval: already reviewed in aosp
Test: m -j CtsNetTestCases
Change-Id: If102677e4cdc4361b5d93283c4d6140dc477a94a
6 files changed
tree: 8cbf42fda69dccfb2955d4e4207809ec22cb40eb
  1. tests/