[MS44.1] Add API to query tagged UID summary

Query tagged UID summary is currently needed by
StatsPullAtomService to collect tagged traffic statistics.
Add an Api via NetworkStatsManager to support this
functionality.

Test: atest NetworkStatsManagerTest
Bug: 204830222
Change-Id: Iaa54482a8109b56e66e829c5bec5a8a8f466641a