www/py-tornado: Update to 6.4

Changes:	https://github.com/tornadoweb/tornado/tree/master/docs/releases
		https://www.tornadoweb.org/en/stable/releases.html

www/py-tornado/Makefile

 PORTNAME=	tornado
-PORTVERSION=	6.3.3
+PORTVERSION=	6.4
 CATEGORIES=	www python
 MASTER_SITES=	PYPI
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}

www/py-tornado/distinfo

-TIMESTAMP = 1692211831
-SHA256 (tornado-6.3.3.tar.gz) = e7d8db41c0181c80d76c982aacc442c0783a2c54d6400fe028954201a2e032fe
-SIZE (tornado-6.3.3.tar.gz) = 509872
+TIMESTAMP = 1710712566
+SHA256 (tornado-6.4.tar.gz) = 72291fa6e6bc84e626589f1c29d90a5a6d593ef5ae68052ee2ef000dfd273dee
+SIZE (tornado-6.4.tar.gz) = 498845