Backfill owner information for VTS module VtsHalHealthV2_1TargetTest.

Each VTS module is required to have OWNERS file. The ownership is based on
go/vts-owners. For more information about ownership policy, please visit
go/xts-owners-policy.

Test: Tree Hugger
Bug: 143903671
Change-Id: I7cba8c0c0fc611d7499c9afdc93d5d6fe865b33a