[PythonBindingsExample] Adjust test fixture to create a new application per test

This ensures that each test completely cleans up after itself, so that
there are no memory leaks.

Signed-off-by: Chris Burel <[email protected]>

Code/Tools/PythonBindingsExample/tests/ApplicationTests.cpp

@@ -29,7 +29,7 @@ namespace PythonBindingsExample
     {
     public:
 
-        static void SetUpTestCase()
+        void SetUp() override
         {
             if (!AZ::AllocatorInstance<AZ::SystemAllocator>::IsReady())
             {
@@ -43,7 +43,7 @@ namespace PythonBindingsExample
             s_application->SetUp();
         }
 
-        static void TearDownTestCase()
+        void TearDown() override
         {
             s_application->TearDown();
             s_application.reset();