Enables memory tracking (leak detection) in more unit tests

Signed-off-by: Esteban Papp <81431996+amznestebanpapp@users.noreply.github.com>

Code/Editor/Lib/Tests/test_TerrainModifyPythonBindings.cpp

@@ -22,7 +22,7 @@ namespace TerrainModifyPythonBindingsUnitTests
 {
 
     class TerrainModifyPythonBindingsFixture
-        : public testing::Test
+        : public UnitTest::ScopedAllocatorSetupFixture
     {
     public:
         AzToolsFramework::ToolsApplication m_app;