Extend feature tests and python versions

[constantinpape]

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[constantinpape]

Mac issue with compute_affinity_features:

 Traceback (most recent call last):
  File "/Users/runner/work/elf/elf/test/segmentation/test_features.py", line 41, in test_compute_affinity_features
    feats = compute_affinity_features(rag, inp, offsets)
  File "/Users/runner/work/elf/elf/elf/segmentation/features.py", line 82, in compute_affinity_features
    features = nrag.accumulateAffinityStandartFeatures(rag, affinity_map, offsets,
RuntimeError: 
Precondition violation!
UserRangeHistogram::update(): setMinMax(...) has not been called.
(/usr/local/miniconda/envs/elf-dev/include/vigra/accumulator.hxx:5935)

Needs to be fixed in nifty.