Merge changes from topic "sp26-networkstats-cts"

* changes:
  [SP26] add CTS for NetworkStats
  [SP26.2] add a method in NetworkStats that removes empty entries
tree: 8a5636fa9367e4f2b4f87c1af5ce07ce69a0f188
  1. core/
  2. services/
  3. tests/