Add test for NetworkAgentConfig

Bug: 139268426
Test: atest CtsNetTestCasesLatestSdk:android.net.NetworkAgentConfigTest
Change-Id: If9158d086bacb0ade94d59898ac223e4c8f4f73a
Merged-In: If9158d086bacb0ade94d59898ac223e4c8f4f73a
(cherry picked from aosp/1253722)
1 file changed