Is there anyway to send message from bot onError

[yuqizhou77]

Use such code snippet in program.cs to have bot send an general message back to users if there is any error happens. However the context is null so that I cannot send message back.

Repro steps:

1. Open Samples.Echo
2. Replace the main method with the content below

    public static void Main(string[] args)
    {
        var builder = WebApplication.CreateBuilder(args);
        builder.Services.AddOpenApi();
        //builder.Services.AddTransient<Controller>();
        builder.AddTeams().AddTeamsDevTools();

        var app = builder.Build();

        if (app.Environment.IsDevelopment())
        {
            app.MapOpenApi();
        }

        app.UseHttpsRedirection();
        var teamsApp = app.UseTeams();

        teamsApp.OnMessage(async (context) =>
        {
            throw new Exception("test exception");
        });

        teamsApp.OnError(async (sender, @event) =>
        {
            Console.WriteLine("!!OnError HIT!!");
            var context = @event.Context;
            await context.Send($"The bot encountered an unhandled error: {@event.Exception.Message}");
            teamsApp.Logger.Error($"[OnError] unhandled error : {@event.Exception.Message}");
        });

        app.Run();
    }

3. context is null that cannot send message.