devel/py-xarray: Update to 2023.8.0

Changes:	https://github.com/pydata/xarray/releases

devel/py-xarray/Makefile

 PORTNAME=	xarray
-PORTVERSION=	2023.7.0
+PORTVERSION=	2023.8.0
 CATEGORIES=	devel python
 MASTER_SITES=	PYPI
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}

devel/py-xarray/distinfo

-TIMESTAMP = 1691070138
-SHA256 (xarray-2023.7.0.tar.gz) = dace2fdbf1b7ff185d9c1226a24bf83c2ae52f3253dbfe80e17d1162600d055c
-SIZE (xarray-2023.7.0.tar.gz) = 3725483
+TIMESTAMP = 1692812434
+SHA256 (xarray-2023.8.0.tar.gz) = 825c6d64202a731a4e49321edd1e9dfabf4be06802f1b8c8a3c00a3ebfc8cedf
+SIZE (xarray-2023.8.0.tar.gz) = 3757528