PATCH submission to accept partial patch rather than full

[drmowinckels]

Currently, the patch submission only accepts the entire submission answer as curl body to alter a submission

existing

{
    "answers": {
        "col1": "value",
        "col2": 1,
        "col3": false,
        "col4": "value"
    }
}

to update:

{
    "answers": {
        "col1": "value",
        "col2": 1,
        "col3": true, \\ <<--- change is here
        "col4": "value"
    }
}

It would have been ideal if patch could accept only the key-value pair you wanted to patch, rather than the entire body.

{
    "answers": {
        "col3": true
    }
}

This should make it easier for users to specify what they want to change. Currently, we"d need to run one get command to get all the data, then change the single value we wanted to patch, before submitting the request with the entire catalogue again.

This would also make the audit logs more succinct and clear, as they would only show the changes, so its easier to spot what has been changed.