Padding lon/lat bounds in _area/_crop_cube returns invalid bounds in extract_region if the geometry is all Earth

[valeriupredoi]

Here - if geometry is as is from esmvalcore/preprocessor/ne_masks/ne_10m_ocean.shp and its bounds are [-179.99999999999991 -85.22193775799991 180.0 90.00000000000006] by padding that will introduce a ValueError: Invalid end_latitude: 90.50000000000006 from extract_region:

Traceback (most recent call last):
  File "test_ne.py", line 49, in <module>
    cube = _crop_cube(cube, *geometries.bounds)
  File "/home/valeriu/ESMValCore/esmvalcore/preprocessor/_area.py", line 340, in _crop_cube
    start_latitude, end_latitude)
  File "/home/valeriu/ESMValCore/esmvalcore/preprocessor/_area.py", line 54, in extract_region
    raise ValueError(f"Invalid end_latitude: {end_latitude}")
ValueError: Invalid end_latitude: 90.50000000000006