public async Task Test_JsonRequestBody_ReturnsOkObjectResult()
        {
            // Arrange
            using var stream =
                      new MemoryStream(
                          System.Text.Encoding.UTF8.GetBytes("{\"name\":\"jan\"}")
                          );

            Mock.Get(request)
            .SetupGet(r => r.Body)
            .Returns(stream);

            // Act
            var response = await GreeterFunction
                           .ExecuteAsync(request, logger)
                           .ConfigureAwait(false);

            // Assert
            Assert.IsInstanceOf <OkObjectResult>(response);
        }