Replace warning with slightly better testing
Replace warning with slightly better testing

Testing LOGWARN was generating a real warning that polluted test output.
Instead, let's catch the warning and test that it actually happens.

smtpd/qpsmtpd,salvis/qpsmtpd,smtpd/qpsmtpd,sieutruc/qpsmtpd,priyadi/qpsmtpd,msimerson/qpsmtpd,sieutruc/qpsmtpd,priyadi/qpsmtpd,salvis/qpsmtpd,msimerson/qpsmtpd,priyadi/qpsmtpd,sieutruc/qpsmtpd