added number_of_frames instead of iterations

[ZohebShaikh]

closes #575

[coretl]

Please can we have a test that looks like the tomography example?

[ZohebShaikh]

I have deleted test_hdf_panda_hardware_triggered_flyable_with_iterations and moved it to

@pytest.mark.parametrize("number_of_frames", [[1, 1, 1, 1], [2, 3, 100, 3]])
async def test_hardware_triggered_flyable(

As we are removing iterations

[evalott100]

I'm happy with this, I think we should wait for a once over from @coretl before we merge.

[evalott100]

I've changed my mind, I'd quite like

#581 (comment)

Which means either:

1)

adding

                self._frames_completed += 1

to complete and removing

        self._frames_completed += self._frames_to_complete

from kickoff.

Or (and I actually think this is the nicer option)

2)

Changing its name to self._completable_frames and leaving a comment in init that it represents the total number of frames that will have been completed at the end of the next complete.

This is nicer because it means that

if self._completable_frames >= self._trigger_info.total_number_of_triggers:
            raise RuntimeError(

will still work - if we changed to increment by 1 then would probably still need this variable to make sure you can't kickoff too many times.