Fixes audio crash and issues w/ audio playback (#1633)

This was caused by the main thread audio update not being called all the
time, especially Editor Game mode.

The crash was due to main thread containers not being processed and
emptied of their requests.

Signed-off-by: amzn-phist <52085794+amzn-phist@users.noreply.github.com>

Code/CryEngine/CryCommon/Mocks/ISystemMock.h

@@ -26,10 +26,6 @@ public:
         bool(int, int));
     MOCK_METHOD0(UpdateLoadtime,
         bool());
-    MOCK_METHOD0(DoWorkDuringOcclusionChecks,
-        void());
-    MOCK_METHOD0(NeedDoWorkDuringOcclusionChecks,
-        bool());
     MOCK_METHOD0(RenderStatistics,
         void());
     MOCK_METHOD0(GetUserName,