Intermitted error in test_datasaver_scalars

```python
@settings(max_examples=5, deadline=None,
suppress_health_check=(HealthCheck.function_scoped_fixture,))
@given(breakpoint=hst.integers(min_value=1, max_value=19),
write_period=hst.floats(min_value=0.1, max_value=1.5),
set_values=hst.lists(elements=hst.floats(), min_size=20, max_size=20),
get_values=hst.lists(elements=hst.floats(), min_size=20, max_size=20))
@pytest.mark.usefixtures('set_default_station_to_none')
def test_datasaver_scalars(experiment, DAC, DMM, set_values, get_values,
breakpoint, write_period):
no_of_runs = len(experiment)

station = qc.Station(DAC, DMM)

meas = Measurement(station=station)
meas.write_period = write_period

assert meas.write_period == write_period

meas.register_parameter(DAC.ch1)
meas.register_parameter(DMM.v1, setpoints=(DAC.ch1,))

with meas.run() as datasaver:
for set_v, get_v in zip(set_values[:breakpoint],
get_values[:breakpoint]):
datasaver.add_result((DAC.ch1, set_v), (DMM.v1, get_v))

assert datasaver._dataset.number_of_results == 0
sleep(write_period * 1.1)
datasaver.add_result((DAC.ch1, set_values[breakpoint]),
(DMM.v1, get_values[breakpoint]))
> assert datasaver.points_written == breakpoint + 1
E assert 0 == (1 + 1)
E + where 0 = .points_written
```

See details in the log below.

[errorlog.txt](https://github.com/QCoDeS/Qcodes/files/9674210/errorlog.txt)

Start with the test_datasaver_scalars test shown in the issue and review errorlog.txt for the intermittent failure details. Reproduce the failure under the test's Hypothesis settings, then identify the relevant DataSaver behavior and verify that the test completes reliably with the expected points_written value.

Written by the indexing model from the issue text.