Add @UnsupportedAppUsage to test apis that are known to be used by apps.

go/testapi-enforcement

Bug: 133832325
Test: m
Change-Id: Ifc8db120640a1554dcbf1722e61e09c7ddc65dd6
Merged-In: Ifc8db120640a1554dcbf1722e61e09c7ddc65dd6

core/java/android/net/NetworkCapabilities.java

@@ -478,6 +478,7 @@ public final class NetworkCapabilities implements Parcelable {
      * @return an array of capability values for this instance.
      * @hide
      */
+    @UnsupportedAppUsage
     @TestApi
     public @NetCapability int[] getCapabilities() {
         return BitUtils.unpackBits(mNetworkCapabilities);