[entity] do not raise an AssertionError if the kwargs given to set_relations/attributes is empty
Regression was introduced in 3.16 with the new cw_set API.
Old set_relations and set_attributes methods did not crash on empty
kwargs.
Closes #3104019.
Latest changes
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* table of `all latest changes`_
Links below is providing useful RQL query example.
.. _all latest changes: view?rql=Any+M%2CX+WHERE+X+modification_date+M+ORDERBY+M+DESC+LIMIT+30