public void Exists_FileDoesNotExist_ReturnsFalse()
        {
            var fileName = "IntegrationTest/NoSuchFile.txt";
            var service  = new S3FileService();

            Assert.IsFalse(service.Exists(fileName));
        }
        public void Exists_FileExists_ReturnsTrue()
        {
            var fileName = "IntegrationTest/MyFile.txt";

            if (!Exists(fileName))
            {
                UploadFile(fileName);
            }

            var service = new S3FileService();

            Assert.IsTrue(service.Exists("MyFile.txt"));
        }