How do i fix the Runtime.ExitError in AWS Lambda (.Net 6 core code invoked by AWS scheduler)?

Question

I created a .Net Core 6 app - HealthCheckerApp, which calls an HTTP GET request to one of my APIs hosted on Api gateway + Lambda to ensure it is accessible. Then, I pushed this code into AWS Lambda and scheduled it to run every minute using the AWS EventBridge Scheduler. It runs the code and gives the successful output, but I can see the Runtime in logs.ExitError after the successful console write. I am not sure why it is causing it. I tried changing Lambda RAM from 128 to 8008 MB, but I got the same error.

Log:

Health check successful!

INIT_REPORT Init Duration: 244.15 ms Phase: invoke Status: error Error Type: Runtime.ExitError

or sometimes:

START RequestId: 2365fc8f-4401-447d-8b3d-3ef00c5be943 Version: $LATEST

RequestId: 2365fc8f-4401-447d-8b3d-3ef00c5be943 Error: Runtime exited without providing a reason

Runtime.ExitError

END RequestId: 2365fc8f-4401-447d-8b3d-3ef00c5be943

REPORT RequestId: 2365fc8f-4401-447d-8b3d-3ef00c5be943 Duration: 245.46 ms Billed Duration: 246 ms Memory Size: 512 MB Max Memory Used: 17 MB

Program.cs:

using System;
using System.Threading.Tasks;

public class Program
{
    public static async Task Main(string[] args)
    {
        try
        {
            var healthChecker = new HealthChecker();
            var isHealthy = await healthChecker.CheckHealthAsync();

            if (isHealthy)
            {
                Console.WriteLine("Health check successful!");
            }
            else
            {
                Console.WriteLine("Health check failed!");
            }

        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error program file: {ex.Message}");
        }
    }
}

HealthChecker.cs

using System;
using System.Net.Http;
using System.Threading.Tasks;

public class HealthChecker
{
    private readonly HttpClient _httpClient;

    public HealthChecker()
    {
        try
        {

            _httpClient = new HttpClient();

        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error http client {ex.Message}");
            throw;
        }
    }

    public async Task<bool> CheckHealthAsync()
    {
        try
        {
            var response = await _httpClient.GetAsync("https://<api gateway custom domain + endpoint>");
            response.EnsureSuccessStatusCode();
            System.Console.WriteLine(await response.Content.ReadAsStringAsync());
            return true;
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error checking health: {ex.Message}");
            return false;
        }
    }
}

The command I used to publish this code and then zipped it to upload: dotnet publish -c Release --self-contained false -r linux-x64 -o publish