[Fixes #5105] Error when using THESAURI

[t-book]

This will stop the error:

File "/Users/ts/github/csgis.geonode/geonode/base/widgets.py", line 33, in __init__
    autocomplete_light.MultipleChoiceWidget(
AttributeError: 'module' object has no attribute 'MultipleChoiceWidget'

From what I see classautocomplete_light.MultipleChoiceWidget is now

classautocomplete_light.widgets.MultipleChoiceWidget(autocomplete=None, widget_js_attributes=None, autocomplete_js_attributes=None, extra_context=None, registry=None, widget_template=None, widget_attrs=None, *args, **kwargs)

@afabiani @capooti this should fix the described issue however I would suggest that we continue here: #5158

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[codecov]

Codecov Report

Merging #5157 into master will not change coverage.
The diff coverage is n/a.

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  Files         185      185           
  Lines       20821    20821           
  Branches     3314     3314           
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  Hits        11175    11175           
  Misses       8635     8635           
  Partials     1011     1011