Fix wait() in @parallel #14150
Description
The new doctesting framework sometimes gets:
sage -t --long devel/sage/sage/homology/simplicial_complex.py
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File "devel/sage/sage/homology/simplicial_complex.py", line 2188, in sage.homology.simplicial_complex.SimplicialComplex.is_cohen_macaulay
Failed example:
S.is_cohen_macaulay(ncpus=3)
Expected:
False
Got:
Exception OSError: (10, 'No child processes') in <generator object __call__ at 0x646f1e0> ignored
False
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Fix this.
Component: misc
Author: Jeroen Demeyer
Reviewer: David Roe
Merged: sage-5.8.beta2
Issue created by migration from https://trac.sagemath.org/ticket/14150