refactor: Deprecate FieldInfo.

[prmukherj]

Deprecate Field Info.

1. Delete from documentation.
2. Update other documentation like FileSession.
3. Updated tests as well

Please refer the updated docs and tests for reference.

# Earlier:
>>> field_info.get_scalar_fields_info
>>> field_info.get_scalar_field_range
>>> field_info.get_vector_fields_info
>>> field_info.get_surfaces_info

# Now:
>>> field_data.scalars()
>>> field_data.vectors()
>>> field_data.surfaces()
>>> field_data.surface_ids()

[prmukherj]

In the vector and scalar fields is it better to add a validator along with is_active check since we don't have field_info exposed to users anymore? The validator can suggest close matching names as well.

[hpohekar]

@prmukherj We need to update doc\deprecated_pyfluent_apis.py.