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>

audio/common/test/utility/include/utility/EnvironmentTearDown.h

@@ -36,7 +36,7 @@ namespace utility {
 class Environment : public ::testing::Environment {
    public:
     using TearDownFunc = std::function<void()>;
-    void registerTearDown(TearDownFunc&& tearDown) { tearDowns.push_back(std::move(tearDown)); }
+    void registerTearDown(TearDownFunc&& tearDown) { tearDowns.push_front(std::move(tearDown)); }
 
    private:
     void TearDown() override {