incorrect metadata in xarray generated by get_data()

[alambare]

cf: CS-SI/eodag#1385 (comment)

[amarandon]

For the record, I noticed that

• the time dimension is renamed to band and its values are changed from dates to integers
• the DataArray returned by eodag-cube is shifted by 180° along the x axis (longitude)

Dataset was obtained with:

search_results = dag.search(
    provider="cop_ads",
    productType="CAMS_EAC4",
    start="2021-01-15",
    end="2021-01-18",
    variable="2m_temperature",
    model_level="1",
    time="00:00",
    format="grib",
)

product = search_results[0]

eodag_da = product.get_data(band=r"\.grib$")
eodag_da[1, 8].plot()

xr_da = xr.open_dataarray(path)
xr_da[1, 8].plot()

[sbrunato]

related to #78