Audio VTS: run tear-down hooks in LIFO instead of FIFO

The audio tests use a static cache of some HAL objects for
performance reasons (speed up by 10x on Pixel).
Those object are destroy during the test environment tear-down.

This tear-down was destroying the objects in a FIFO instead of LIFO
order. Thus the DeficesFactory was destroyed before the Device it
created.

Bug: 79889318
Test: vts-tradefed run commandAndExit vts --module VtsHalAudioV2_0Target
      check that the device destructor is called before the
      devicesFactory one.
Change-Id: I1b4345158139ba14a8779a9508f7ebdc41129d1d
Signed-off-by: Kevin Rocard <krocard@google.com>