Skip NetworkAgentTest on R-

NetworkAgent is not updatable on R-, so there is no need to run tests
compiled against S on older platforms. They are also incompatible
because NetworkAgent stopped using AsyncChannel in S.

This only affects MTS, and CTS used to test S+ devices. CTS for R-
devices is already cut in a branch that this change will not merge to.

Bug: 177290955
Change-Id: I85c137a1b5fd7ef701fba4623566df5a8fb707a3
Test: atest CtsNetTestCasesLatestSdk
diff --git a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
index 803c9d8..69d90aa 100644
--- a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
+++ b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
@@ -126,7 +126,7 @@
 @RunWith(AndroidJUnit4::class)
 class NetworkAgentTest {
     @Rule @JvmField
-    val ignoreRule = DevSdkIgnoreRule(ignoreClassUpTo = Build.VERSION_CODES.Q)
+    val ignoreRule = DevSdkIgnoreRule(ignoreClassUpTo = Build.VERSION_CODES.R)
 
     private val LOCAL_IPV4_ADDRESS = InetAddresses.parseNumericAddress("192.0.2.1")
     private val REMOTE_IPV4_ADDRESS = InetAddresses.parseNumericAddress("192.0.2.2")