Fix GitHub actions update for Sphinx 8 / Python 13

[shaloo]

GitHub actions for push are failing due to python upgrade / Sphinx upgrade

Need to debug and figure out appropriate GH actions that support the required combination of dependencies.

[shaloo]

https://github.com/c3g/GenPipes/actions

[shaloo]

https://github.com/c3g/GenPipes/actions/runs/11736584911

[shaloo]

Fixed: https://github.com/c3g/GenPipes/actions/runs/11957547322, https://github.com/c3g/GenPipes/actions/runs/11955290417

[shaloo]

cc: @paulstretenowich thx for the Mac OS Python 3.13 action tip. It builds the Mac action but there are still issues in accessing one of the enchant libraries used by spell checker. The issue does not happen on linux. For now, I have enabled spell checking in Linux action. Mac action is just build sanity.