GetWebApplicationFactory.cs

private WebApplicationFactory<Program> GetWebApplicationFactory() =>
    new WebApplicationFactory<Program>()
        .WithWebHostBuilder(builder =>
        {
            IConfigurationSection? configSection = null;
            builder.ConfigureAppConfiguration((context, config) =>
            {
                config.AddJsonFile(Path.Combine(Directory.GetCurrentDirectory(), AppSettingsFile));
                configSection = context.Configuration.GetSection(nameof(WeatherDatabaseSettings));
            });
            builder.ConfigureTestServices(services =>
                services.Configure<WeatherDatabaseSettings>(configSection));
        });