devel/py-distributed: Update to 2021.6.0

Changes:	https://github.com/dask/distributed/blob/main/docs/source/changelog.rst
		https://distributed.dask.org/en/latest/changelog.html

devel/py-distributed/Makefile

 # Created by: Po-Chuan Hsieh <sunpoet@FreeBSD.org>
 
 PORTNAME=	distributed
-PORTVERSION=	2021.5.0
+PORTVERSION=	2021.6.0
 CATEGORIES=	devel python
 MASTER_SITES=	CHEESESHOP
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}

devel/py-distributed/distinfo

-TIMESTAMP = 1621183206
-SHA256 (distributed-2021.5.0.tar.gz) = 4da09db7972120db0a8e7fc2b2f91bb4d952ce21b185ccc1356603613060a0b3
-SIZE (distributed-2021.5.0.tar.gz) = 717781
+TIMESTAMP = 1622214066
+SHA256 (distributed-2021.6.0.tar.gz) = 0ad3db5d2618fc29291b02e8ebc7a1ff6cfce5013455143c3e1bce438b2b5a48
+SIZE (distributed-2021.6.0.tar.gz) = 732659