/// <summary>
 /// Runs the specified fixture action if a property exists in the fixture that matches the specified value.
 /// </summary>
 /// <param name="fixture">The fixture.</param>
 /// <param name="key">The key.</param>
 /// <param name="value">The value.</param>
 /// <param name="action">The action.</param>
 /// <returns></returns>
 public static ITestFixture WhenHavingStringProperty(this ITestFixture fixture,
                                                     string key,
                                                     string value,
                                                     Action <ITestFixture> action) =>
 fixture.WhenHavingStringProperty(key, x => x == value, action);