Fix lint issues in NetworkAgentTest.kt.

The linter is complaining about the import ordering.

Bug: 143158421
Test: TH (no code changes)
Change-Id: If9fefb9ece86fa24cb4b3f28c088c0b6820a1049
diff --git a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
index b535a8f..869562b 100644
--- a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
+++ b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
@@ -108,17 +108,6 @@
 import com.android.testutils.TestableNetworkAgent.CallbackEntry.OnValidationStatus
 import com.android.testutils.TestableNetworkCallback
 import com.android.testutils.assertThrows
-import org.junit.After
-import org.junit.Before
-import org.junit.Test
-import org.junit.runner.RunWith
-import org.mockito.ArgumentMatchers.any
-import org.mockito.ArgumentMatchers.argThat
-import org.mockito.ArgumentMatchers.eq
-import org.mockito.Mockito.doReturn
-import org.mockito.Mockito.mock
-import org.mockito.Mockito.timeout
-import org.mockito.Mockito.verify
 import java.io.Closeable
 import java.io.IOException
 import java.net.DatagramSocket
@@ -136,6 +125,17 @@
 import kotlin.test.assertNull
 import kotlin.test.assertTrue
 import kotlin.test.fail
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentMatchers.any
+import org.mockito.ArgumentMatchers.argThat
+import org.mockito.ArgumentMatchers.eq
+import org.mockito.Mockito.doReturn
+import org.mockito.Mockito.mock
+import org.mockito.Mockito.timeout
+import org.mockito.Mockito.verify
 
 // This test doesn't really have a constraint on how fast the methods should return. If it's
 // going to fail, it will simply wait forever, so setting a high timeout lowers the flake ratio