REF: removed old fsl command
REF: removed old fsl command

Former-commit-id: a15724e860b47f818f53c524be28df5b129bcfbe
Former-commit-id: 33f2f1d3dc5cea036461ff81484679d734598ef8
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox