Use type annotations to obviate the use of ``_or_`` in function argument names

[rileyjmurray]

While working on another PR I started to add type annotations to the run_long_sequence_gst function in drivers/longsequence.py. I found that argument names could be simplified considerably in the process. For example, the current signature is

def run_long_sequence_gst(data_filename_or_set, target_model_filename_or_object,
                          prep_fiducial_list_or_filename, meas_fiducial_list_or_filename,
                          germs_list_or_filename, max_lengths, gauge_opt_params=None,
                          advanced_options=None, comm=None, mem_limit=None,
                          output_pkl=None, verbosity=2, checkpoint=None, checkpoint_path=None,
                          disable_checkpointing=False,
                          simulator: Optional[ForwardSimulator.Castable]=None,
                          gauge_opt_suite_name: str = 'stdgaugeopt'):

while a type-annotated signature could be

FileName = str  # a type alias with clear semantic meaning

def run_long_sequence_gst(
        data: Union[FileName, DataSet], target_model: Union[FileName, _Model],
        prep_fiducials: Union[FileName, Sequence[Circuit]], 
        meas_fiducials: Union[FileName, Sequence[Circuit]],
        germs: Union[FileName, Sequence[Circuit]],
        max_lengths: Sequence[int], gauge_opt_params=None,
        advanced_options: Optional[dict[str, Any]]=None, comm=None, mem_limit=None,
        output_pkl=None, verbosity=2, checkpoint=None, checkpoint_path=None,
        disable_checkpointing=False,
        simulator: Optional[ForwardSimulator.Castable]=None,
        gauge_opt_suite_name: str = 'stdgaugeopt'):

I'm not going to propose these changes in my other PR, since that would complicate reviews. Making it note of this here so we can address it later.

[rileyjmurray]

Here's a regex heuristic for finding offending arguments: def [^\\n]+[a-zA-Z]*_or_[a-zA-Z]*.