mail/py-python-slimta: Unbreak import with FreeBSD Python

In order to retain compatibility with Python 2, mail/py-python-slimta mandates
an older version of mail/py-pysasl than what is in Ports. However, lang/python27
has expired so there should be no compatibility issues with FreeBSD.

Reviewed by:		0mp (mentor)
Approved by:		0mp (mentor)
Differential Revision:	https://reviews.freebsd.org/D28051

mail/py-python-slimta/Makefile

@@ -2,6 +2,7 @@
 
 PORTNAME=	python-slimta
 PORTVERSION=	4.1.1
+PORTREVISION=	1
 CATEGORIES=	mail
 MASTER_SITES=	CHEESESHOP
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}

mail/py-python-slimta/files/patch-setup.py

@@ -0,0 +1,11 @@
+--- setup.py.orig	2021-01-08 23:33:01 UTC
++++ setup.py
+@@ -40,7 +40,7 @@ setup(name='python-slimta',
+       packages=find_packages(),
+       namespace_packages=['slimta'],
+       install_requires=['gevent >= 1.1rc',
+-                        'pysasl >= 0.4.0, < 0.5',
++                        'pysasl >= 0.4.0',
+                         'pycares < 3.0.0; python_version < "3.0"',
+                         'pycares >= 1; python_version >= "3.0"'],
+       extras_require={'spf': ['pyspf', 'py3dns; python_version >= "3.0"',