Cosmetic fixes on -list-tasks

[jcohenadad]

Checklist

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Description

Fixes #3776

Linked issues

[codecov]

Codecov Report

Merging #3777 (3119675) into master (bad5780) will not change coverage.
The diff coverage is 0.00%.

Flag	Coverage Δ
api-tests	22.51% <0.00%> (+<0.01%)	⬆️
cli-tests	58.50% <0.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
spinalcordtoolbox/deepseg/models.py	56.00% <0.00%> (ø)

[joshuacwnewton]

The changes look good to me, visually! Thank you for this. :)

Before:

After:

(Please disregard the color issue, see #3780)