ActionHistory_V3.cs singleton pattern

ActionHistory_V3.cs

public class ActionHistory_V3 : IActionHistory
{
    private static Lazy<ActionHistory_V3> instance =
                    new Lazy<ActionHistory_V3>(() => new ActionHistory_V3());
    public static ActionHistory_V3 Instance { get; } = instance.Value;

    private ActionHistory_V3()
    {
        ....
    }
    
    ....
}