Account for futures = None

[Bisho2122]

If futures is None then it will trigger the error TypeError: 'NoneType' object is not iterable in self._perf.record_entry. So It was changed so that it wouldn't raise the type error and instead continue to raise the exception captured earlier.

This was suggested based on the following traceback for a dataset :

  File "/opt/dev/metaspace/metaspace/engine/sm/engine/daemons/lithops.py", line 112, in _callback
    self._manager.annotate_lithops(
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/daemons/dataset_manager.py", line 127, in annotate_lithops
    job.run()
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/annotation_job.py", line 341, in run
    self.results_dfs, self.png_cobjs, self.enrichment_data = self.pipe.run_pipeline(
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/pipeline.py", line 103, in run_pipeline
    self.load_ds(use_cache=use_cache)
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/cache.py", line 81, in wrapper
    return f(self, *args, **kwargs)
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/pipeline.py", line 155, in load_ds
    ) = load_ds(
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/load_ds.py", line 225, in load_ds
    (imzml_reader, ds_segments_bounds, ds_segms_cobjs, ds_segm_lens,) = executor.call(
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/executor.py", line 407, in call
    return self.map(
  File "/opt/dev/metaspace/metaspace/engine/sm/engine/annotation_lithops/executor.py", line 278, in map
    request_ids=[f.activation_id for f in futures],  # pylint: disable=not-an-iterable
TypeError: 'NoneType' object is not iterable