Bug#1050854: xarray test failure on amd64

[Rebecca N. Palmer]

I have added what should be fixes for #1053700 and #1044869, but they 
are currently untested as salsa-ci only runs the autopkgtest on amd64. 
#1050854 appears to have been fixed (or at least xfailed - it passed on 
salsa-ci but they say it's flaky) by upstream.