`-add-seg-only` generates JSON sidecars with `"Name": "Manual"`

When using manual-correction.py -add-seg-only to copy the source segmentations (i.e., automatically generated (e.g., by sct_deepseg_sc or SCIseg) and visually verified in HTML QC) to the final git-annex dataset, manual-correction.py generates the following JSON sidecar containing "Name": "Manual", for example:

{
    "SpatialReference": "orig",
    "GeneratedBy": [
        {
            "Name": "Manual",
            "Author": "Jan Valosek",
            "Date": "2024-02-02 08:50:37"
        }
    ]
}

But since the segmentations were generated automatically, e.g., by sct_deepseg_sc or SCIseg, the JSON should rather look like:

{
    "SpatialReference": "orig",
    "GeneratedBy": [
        {
            "Name": "SCIseg nnUNet3D",
            "Version": "https://github.com/ivadomed/model_seg_sci/releases/tag/r20240130",
            "Date": "2024-02-01"
        }
    ]
}

spinalcordtoolbox / manual-correction

`-add-seg-only` generates JSON sidecars with `"Name": "Manual"` #78