public async Task GetFieldsAsync_ShouldReturnEmptyList_CollectionIsEmpty()
        {
            // Act
            var actual = await _sut.GetFieldsAsync(new []
            {
                new BsonDocument
                {
                    ["_id"]   = Fixture.Create <string>(),
                    ["Value"] = Fixture.Create <string>(),
                }
            }, null, CancellationToken.None);

            // Assert
            actual.Should().BeEmpty();
        }