Expose sticky select option to the SettingsRegistry and disable by default (#4149)

* expose sticky select option to the SettingsRegistry

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* update missed callsites after API change to Manipulator Test Framework

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* updates following review feedback

Signed-off-by: hultonha <hultonha@amazon.co.uk>

Code/Framework/AzManipulatorTestFramework/Tests/GridSnappingTest.cpp

@@ -76,7 +76,7 @@ namespace UnitTest
                 linearManipulator->SetLocalPosition(action.LocalPosition());
             });
 
-        m_actionDispatcher->EnableSnapToGrid()
+        m_actionDispatcher->SetSnapToGrid(true)
             ->GridSize(5.0f)
             ->CameraState(m_cameraState)
             ->MousePosition(initialPositionScreen)
@@ -114,7 +114,7 @@ namespace UnitTest
                 manipulator->SetLocalPosition(action.LocalPosition());
             });
 
-        actionDispatcher->EnableSnapToGrid()
+        actionDispatcher->SetSnapToGrid(true)
             ->GridSize(1.0f)
             ->CameraState(cameraState)
             ->MousePosition(initialPositionScreen)