bug#42720: 28.0.50; mml-first-secure-en-decrypt-sign-1 test failing on Fedora 31

[Stefan Kangas]

Paul Eggert <eggert@cs.ucla.edu> writes:

> Would that cause 'make check' to work? If so, I guess it's good enough. 
> Another
> option would be to disable the test.

Yes, then it would only be run on `make check-all'.