Upgrade setuptools to avoid issue with egg_info

[fflorent]

Problem

• I cannot install borg_ynh, because:

Attention :   Cache entry deserialization failed, entry ignored
Attention : Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-install-rfl1lboe/borgbackup/
Erreur : Impossible d’installer borg : Une erreur est survenue dans le script d’installation de l’application

Solution

• Upgrade setuptools, as explained here: https://appuals.com/command-python-setup-py-egg_info/

PR Status

• [x] Code finished and ready to be reviewed/tested
• [x] The fix/enhancement were manually tested (if applicable)

Automatic tests

Automatic tests can be triggered on https://ci-apps-dev.yunohost.org/ after creating the PR, by commenting "!testme", "!gogogadgetoci" or "By the power of systemd, I invoke The Great App CI to test this Pull Request!". (N.B. : for this to work you need to be a member of the Yunohost-Apps organization)

[fflorent]

I see that the change is integrated, I close the PR.

Thanks! :)