style: black

Hello dear contributors,

This is an auto generated modification to help you improve the code base of logilab. If this commit is bad don't hesitate to close this MR and report it here https://forge.extranet.logilab.fr/cubicweb/cube-doctor/-/issues.

Kind regards,

added To Review label

enabled an automatic merge when the pipeline for 657e887a4d80 succeeds

merged