Update python-xarray to version 2022.6.0 / rev 37 via SR 997996
    
    https://build.opensuse.org/request/show/997996
    by user mcalabkova + dimstar_suse
    - specfile:
      * updated requirements versions
      * added new requirements: packaging and flox (recommends)
      * require python >= 3.8
      * update line numbers in patches
      * changed README.rst->README.md
    - update to version 2022.6.0:
      * This release brings a number of bug fixes and improvements, most
        notably a major internal refactor of the indexing functionality,
        the use of flox in groupby operations, and experimental support
        for the new Python Array API standard. It also stops testing
        support for the abandoned PyNIO.
      * Much effort has been made to preserve backwards compatibility as
        part of the indexing refactor. We are aware of one unfixed issue.
      * New Features
        + Add Dataset.dtypes, core.coordinates.DatasetCoordinates.dtypes,
          core.coordinates.DataArrayCoor