Add test for IpConfiguration and also address review
comments from aosp/1171795.
Bug: 139268426
Test: CtsNetTestCasesLatestSdk:android.net.cts.IpConfigurationTest
Change-Id: Ib30a98e11bdcd9d473b713f7e4c317172b14f000
Merged-In: Ib30a98e11bdcd9d473b713f7e4c317172b14f000
(cherry picked from commit 8e208eb353263bddca4d93a7a67a5f978316b0cc)