security/py-fail2ban: Fix runtime error with Python 3.9

PR: 250356
Submitted by: Yasuhiro KIMURA <yasu@utahime.org>
Approved by: theis@gmx.at (maintainer)
Obtained from: https://bugzilla.redhat.com/show_bug.cgi?id=1808347
Obtained from: https://github.com/fail2ban/fail2ban/issues/2646
Obtained from: https://github.com/fail2ban/fail2ban/pull/2651