Disable CtsNetTestCases if needed

Apply NetworkStackNextEnableDefaults to CtsNetTestCases to disable it
in branches where NetworkStackNext and related targets should not be
built.

Test: presubmit
Change-Id: I850b4294aa4c3c01f8871760185ca7fedc0f8584
diff --git a/tests/cts/net/Android.bp b/tests/cts/net/Android.bp
index 1872327..81c30b1 100644
--- a/tests/cts/net/Android.bp
+++ b/tests/cts/net/Android.bp
@@ -69,7 +69,7 @@
 // devices.
 android_test {
     name: "CtsNetTestCases",
-    defaults: ["CtsNetTestCasesDefaults"],
+    defaults: ["CtsNetTestCasesDefaults", "NetworkStackNextEnableDefaults"],
     // TODO: CTS should not depend on the entirety of the networkstack code.
     static_libs: [
         "NetworkStackApiCurrentLib",