Update visibility to for net cts to use shims

Net cts in packages/modules/Connectivity will need to use
the shims to control the tests flow. Expose the visibility
to share with connectivity module.

Bug: 167645754
Test: m NetworkStack NetworkStackNext
Change-Id: I71ea9098c0ae68a849bcf751f717566c26094ced
diff --git a/Android.bp b/Android.bp
index 83bcd91..149245e 100644
--- a/Android.bp
+++ b/Android.bp
@@ -140,7 +140,9 @@
         "NetworkStackApi31Shims",
     ],
     sdk_version: "module_current",
-    visibility: ["//visibility:private"],
+    visibility: [
+        "//packages/modules/Connectivity/tests/cts/net",
+    ],
 }
 
 // API stable uses jarjar to rename the latest stable apishim package from
@@ -156,7 +158,9 @@
     ],
     jarjar_rules: "apishim/jarjar-rules-compat.txt",
     sdk_version: "system_30",
-    visibility: ["//visibility:private"],
+    visibility: [
+        "//packages/modules/Connectivity/tests/cts/net",
+    ],
 }
 
 // Common defaults for android libraries containing network stack code, used to compile variants of