BUG: fixed bug on sct_propseg
BUG: fixed bug on sct_propseg

Former-commit-id: 7dda4341f5d64f36452a9081fa8345d6240e1445
Former-commit-id: 4c4d8eda297ec10cb68410bae9987484ac61cd4c
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox