snfeatures unit test failing

[Catarina-Alves]

The results of test_karpenka_leastsq and test_newling_leastsq changed with the update of some library. I could not diagnose what changed and test_karpenka_leastsq is now failing because the changes are larger than the tolerance.

The tests test_templates_leastsq and test_newling_leastsq also need to be fixed due to the same motive

At the moment, the failing tests are commented out but we should investigate what changed, why and decide whether to update the test or change it somehow.

File: snfeatures_test.py
Functions: test_karpenka_leastsq, test_templates_leastsq, test_newling_leastsq