Update GraphModelIntegrationTests's GetNodesFromGraphNodeIds test to reflect new behavior of the function.

GetNodesFromGraphNodeIds no longer adds null pointers to the list it returns, so the test was updated to reflect that only one item - the valid item - should be returned from the function.

Signed-off-by: Andre Mitchell <andre.mitchell@bytesofpi.com>

Gems/GraphModel/Code/Tests/GraphModelIntegrationTest.cpp

@@ -173,16 +173,11 @@ namespace GraphModelIntegrationTest
         };
         GraphModel::NodePtrList retrievedNodes;
         GraphModelIntegration::GraphControllerRequestBus::EventResult(retrievedNodes, m_sceneId, &GraphModelIntegration::GraphControllerRequests::GetNodesFromGraphNodeIds, nodeIds);
-        EXPECT_EQ(nodeIds.size(), retrievedNodes.size());
+        // Test that only one node was found.
+        EXPECT_EQ(retrievedNodes.size(), 1);
 
         // Test the first node in the list should be our valid test node
         EXPECT_EQ(retrievedNodes[0], testNode);
-
-        // Test the second node should be a nullptr since it was an invalid NodeId
-        EXPECT_EQ(retrievedNodes[1], nullptr);
-
-        // Test the third node should also be a nullptr since it was a valid NodeId but one that doesn't exist in the scene
-        EXPECT_EQ(retrievedNodes[2], nullptr);
     }
 
     TEST_F(GraphModelIntegrationTests, ExtendableSlotsWithDifferentMinimumValues)