Forwarded request #1152304 from bnavigator

- Update to 2024.2.0
* This release brings size information to the text repr, changes
to the accepted frequency strings, and various bug fixes.
## New Features
* Added a simple nbytes representation in DataArrays and Dataset
repr. (GH8690, PR8702). By Etienne Schalk.
* Allow negative frequency strings (e.g. "-1YE"). These strings
are for example used in date_range(), and cftime_range()
(PR8651). By Mathias Hauser.
* Add NamedArray.expand_dims(), NamedArray.permute_dims() and
NamedArray.broadcast_to() (PR8380) By Anderson Banihirwe.
* Xarray now defers to flox’s heuristics to set the default
method for groupby problems. This only applies to flox>=0.9. By
Deepak Cherian.
* All quantile methods (e.g. DataArray.quantile()) now use
numbagg for the calculation of nanquantiles (i.e., skipna=True)
if it is installed. This is currently limited to the linear
interpolation method (method=’linear’). (GH7377, PR8684) By
Marco Wolsza.
## Breaking changes
* infer_freq() always returns the frequency strings as defined in
pandas 2.2 (GH8612, PR8627). By Mathias Hauser.
* Deprecations
* The dt.weekday_name parameter wasn’t functional on modern
pandas versions and has been removed. (GH8610, PR8664) By Sam
Coleman.
## Bug fixes
* Fixed a regression that prevented multi-index level coordinates
being serialized after resetting or dropping the multi-index
(GH8628, PR8672). By Benoit Bovy.