scripts: west: cherry-pick upstream 321ab2e17

Bring in the changes from upstream 321ab2e17 ("runner: core: fix
docstrings for ReST integration"). This is a minimal change necessary
to avoid documentation build issues. The rest of West has gained other
features that are too late to pull in to the RC period, so just bring
in what's needed to get to v1.12.

Signed-off-by: Marti Bolivar <marti@opensourcefoundries.com>