sysutils/py-salt: python3.8 is not supported yet

https://docs.saltstack.com/en/2019.2/topics/installation/index.html#dependencies
https://docs.saltstack.com/en/3000/topics/releases/3000.html#python-3-8-not-supported
saltstack/salt#55310

PR:		243610
Reported by:	Tommy P <tommyhp2@gmail.com>
Approved by:	Christer Edwards <christer.edwards@gmail.com> (maintainer)


git-svn-id: svn+ssh://svn.freebsd.org/ports/head@527918 35697150-7ecd-e111-bb59-0022644237b5

sysutils/py-salt/Makefile

@@ -26,7 +26,7 @@ RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}Jinja2>0:devel/py-Jinja2@${PY_FLAVOR} \
 		${PYTHON_PKGNAMEPREFIX}yaml>0:devel/py-yaml@${PY_FLAVOR} \
 		${PYTHON_PKGNAMEPREFIX}pyinotify>0:devel/py-pyinotify@${PY_FLAVOR}
 
-USES=		cpe python
+USES=		cpe python:-3.7
 
 CPE_VENDOR=	saltstack
 CPE_PRODUCT=	salt