appstart.cs

public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.ConfigureAppConfiguration(config =>
                    {
                        config.AddAzureAppConfiguration(appConfig =>
                        {
                            var credential = new ManagedIdentityCredential("93e93c24-c457-4dea-bee3-218b29ae32f1");

                            appConfig.Connect(new Uri(AppConfigUrl), credential)
                                .ConfigureKeyVault(kvConfig =>
                                {
                                    kvConfig.SetCredential(credential);
                                });
                        });
                    }).UseStartup<Startup>();
                });