BIDS 1.4+ dataset_description.json update

[pierre-nedelec]

QSIprep creates dataset_description.json automatically, however newer BIDS versions (1.4+) require the "GeneratedBy" key. Value is a list, with the same key-values as the original "PipelineDescription". e.g.:

{
    "Name": "qsiprep output",
    "BIDSVersion": "1.1.1",
    "PipelineDescription": {
        "Name": "qsiprep",
        "Version": "0.19.0",
        "CodeURL": "https://github.com/pennbbl/qsiprep/archive/0.19.0.tar.gz"
    },
    "GeneratedBy": [{
        "Name": "qsiprep",
        "Version": "0.19.0",
        "CodeURL": "https://github.com/pennbbl/qsiprep/archive/0.19.0.tar.gz"
    }],
    "CodeURL": "https://github.com/pennbbl/qsiprep",
    "HowToAcknowledge": "Please cite our paper (https://www.nature.com/articles/s41592-021-01185-5#citeas), and include the generated citation boilerplate within the Methods section of the text."
}