Ensure that 0D numpy arrays are unpacked when filling lazy loaded IDS from netCDF files

[maarten-ic]

>>> entry = imas.DBEntry("ascii.nc", "r")
>>> eq = entry.get("equilibrium", autoconvert=False, lazy=True)
>>> # Previous behaviour:
>>> eq.ids_properties.homogeneous_time
<IDSInt0D (IDS:equilibrium, ids_properties/homogeneous_time, INT_0D)>
ndarray(array(1, dtype=int32))
>>> # New behaviour, matches with non-lazy IDS:
>>> eq.ids_properties.homogeneous_time
<IDSInt0D (IDS:equilibrium, ids_properties/homogeneous_time, INT_0D)>
int(1)