public void AddDockerSecrets(string configKey, string expected)
{
var configurationBuilder = new TestConfigurationBuilder();
Assert.Empty(configurationBuilder.Sources);
configurationBuilder
.AddDockerSecrets();
Assert.NotEmpty(configurationBuilder.Sources);
var configuration = configurationBuilder.Build();
var actual = configuration.GetValue <string>(configKey);
Assert.NotNull(actual);
Assert.Equal(expected, actual);
}