REF: adapted gmseg dataset preprocessing to new interpolation options in sct_resample
REF: adapted gmseg dataset preprocessing to new interpolation options in sct_resample

Former-commit-id: c0bf2c91b6e02d59ef1071c303643fe3604f5214
Former-commit-id: 459d2d345af098881f8796f69eafc216796665ba
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox