python-xarray: autopkgtest regression with pytest 8

Imported from Debian bug http://bugs.debian.org/1063981:

Package: python-xarray
Version: 2023.12.0-3
Severity: important
User: <email address hidden>
Usertags: pytest-8

Dear maintainer,

your package has a autopkgtest regression with pytest 8.

Typically, packages will start failing if they

- have deprecation warnings of type PytestRemovedIn8Warning, or

- assume a particular pytest stdout/stderr output which might have
changed, or

- rely on implementation details of the pytest test collector, in
particular the pytest.Package class, which has been redesigned for
pytest 8.

Please refer to the upstream changelog [1] for a complete list of
breaking changes and the pytest (pseudo-)excuses [2] related to your
package for details of the regression.

It is possible that the autopkgtest regression is not directly caused
by python-xarray, but by one of its dependencies. In that case, feel
free to reassign the bug and mark your package as affected, but do
not close the bug until the autopkgtest passes.

Cheers Timo

[1]
https://docs.pytest.org/en/8.0.x/changelog.html#pytest-8-0-0rc1-2023-
12-30 [2]
https://qa.debian.org/excuses.php?experimental=1&package=pytest