[automerger skipped] Add CTS test for NetworkAgent/NetworkAgentConfig API am: 42096be0c6 am: 396c9afb65 -s ours

am skip reason: Merged-In Ia67b963b8e18af8440b1b9bd91f53439848bb838 with SHA-1 561547a537 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/15009311

Change-Id: I053df5078bfe543d41d21b1c2cc93a218ad9a622