Remove @hide usage in DataUsageUtilsTest

Replace matchesSubscriberId with an equivalent check based on the stable
API getSubscriberIds().

Bug: 197717846
Test: atest DataUsageUtilsTest
  (cherry-picked from ag/16801786)
Change-Id: Icf86598dc2e4e8b24e08135de8a842f52ac4ab5b
Merged-In: Icf86598dc2e4e8b24e08135de8a842f52ac4ab5b
1 file changed