Add ServiceConnectivityResources to tethering

The resource package is used by service-connectivity to load its own
resources.

Bug: 182125649
Test: atest FrameworksNetTests
Ignore-AOSP-First: Need to merge manually in relevant branches

Change-Id: I3c7fc6285f10318ecef05a64e1179054bb831d99

Tethering/apex/Android.bp

@@ -35,7 +35,10 @@ apex {
         "offload.o",
         "test.o",
     ],
-    apps: ["Tethering"],
+    apps: [
+        "ServiceConnectivityResources",
+        "Tethering",
+    ],
     manifest: "manifest.json",
     key: "com.android.tethering.key",