Help fixing #959558 (case: FTBFS: AttributeError: 'tuple' object has no attribute 'lstrip' with sphinx 2.4)

[Thomas Goirand]

Hi there!

Does any of you knows how to fix this bug?
https://bugs.debian.org/959558

Almost all of OpenStack can removed from Bullseye if not fixed in time,
so I tried to fix, but couldn't.

Cheers,

Thomas Goirand (zigo)