Allow hidden connectivity APIs in net test utils

The net test utils are used for unit tests exercising connectivity code,
and need access to its hidden APIs.

Bug: 182859030
Test: atest NetworkStaticLibTests
Ignore-AOSP-First: needs manual cherry-picks
Change-Id: I33273e5c1cc2731443f0fd745ce526473a704520
diff --git a/staticlibs/tests/unit/Android.bp b/staticlibs/tests/unit/Android.bp
index 45a89b0..c9aad71 100644
--- a/staticlibs/tests/unit/Android.bp
+++ b/staticlibs/tests/unit/Android.bp
@@ -10,6 +10,7 @@
     name: "NetworkStaticLibTestsLib",
     srcs: ["src/**/*.java","src/**/*.kt"],
     min_sdk_version: "29",
+    defaults: ["framework-connectivity-test-defaults"],
     static_libs: [
         "net-utils-framework-common",
         "androidx.test.rules",