[Flexiglass] Fix KTF filter for instant reversed transitions

When in STL A -> B settles in A we can't do the same in KTF as KTF
requires us to start B -> A to get back to A.
[LockscreenSceneTransitionInteractor] will emit these steps but because
STL is Idle(A) at this point (and never even started a B -> A in the
first place) [isTransitioningBetweenDesiredScenes] will not be satisfied
. We need this condition to not filter out the STARTED and FINISHED step
 of the "artificially" reversed B -> A transition.

Test: tested manually cancelling the LS -> Bouncer transition
Bug: 379845752
Flag: com.android.systemui.scene_container
Change-Id: I289ae405ec792e3d31fd9d303acb8dc4fc85df28