OPT: do not output qc when registering images with sct_segment_gm code
OPT: do not output qc when registering images with sct_segment_gm code

Former-commit-id: 0d7d6d6073ebd292c1543a148fd591cea9023f32
Former-commit-id: 5356c199a3e5c8cdc990afb5d5b2c279f3987edb
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox