Your bug report

#28095: Graphviz test-suite probably requires ksh-93

which was filed against the guix package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 28095@debbugs.gnu.org.

-- 
28095: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=28095
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