Bug#1050854: xarray test failure on amd64

[Rebecca N. Palmer]

This bug is now a crash (not the original error message):
https://ci.debian.net/data/autopkgtest/testing/amd64/p/python-xarray/39962554/log.gz
I don't know whether the same patch still works.

The Salsa repository now appears to be up to date.

You probably also want to include the fixes for the other two RC bugs 
(see there).