使用TFS Rest API可从curl运行，但不能从客户端dotnet库运行

using System;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;

class Program
{
    static async System.Threading.Tasks.Task Main(string[] args)
    {
        string tfsUrl = "https://your-tfs-url/_apis";
        string username = "your-username";
        string password = "your-password";

        using (HttpClient client = new HttpClient())
        {
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
                Convert.ToBase64String(System.Text.ASCIIEncoding.ASCII.GetBytes($"{username}:{password}")));

            HttpResponseMessage response = await client.GetAsync($"{tfsUrl}/versioncontrol");
            if (response.IsSuccessStatusCode)
            {
                string responseBody = await response.Content.ReadAsStringAsync();
                Console.WriteLine(responseBody);
            }
            else
            {
                Console.WriteLine($"Failed to get data: {response.StatusCode}");
            }
        }
    }
}

client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));