Fix GattServiceTests that depend on previous GattService flow

When the flag is set as true and cleaned up, these tests will be
removed.

Test: atest GattServiceTest
Bug: 341972436
Bug: 351943578
Bug: 313335632
Bug: 267361243
Bug: 327503826
Change-Id: Ibd48ae5295c13c7171786d33ae13090aaf6ad2d4