Fix enter-desktop-by-drag cuj to only cancel when aborted.

Fix the CUJ_DESKTOP_MODE_ENTER_APP_HANDLE_DRAG_RELEASE interaction as it
was showing up as cancelled even when the transition finished correctly.

Test: DragToDesktopTransitionHandlerTest & Perfetto trace.
Bug: 357811393
Flag: com.android.window.flags.enable_desktop_windowing_mode
Change-Id: I8ebebc10cd141098665dc93536500651213a4df3