ModesDndTile: Drop usages of runBlocking

- This CL refactors ModesDndTile to drop use of runBlocking.
  Previously, runBlocking was used to call userActionInteractor's
  handleClick() method which could take up time and block the main
  thread.
- We now do this asynchronously via lifecycleScope. While
  lifecycleScope also uses the main thread internally, we do not block
  the main thread anymore. Additionally, the life of this coroutine is
  managed by the lifecycle of the Tile.

Bug: 423462317
Flag: com.android.systemui.do_not_use_run_blocking
Test: atest ModesDndTileTest
Change-Id: I317e6d4c82e0f62296a00b7ca965bf051e248beb