message: Add test for group onPropChange
diff: @@ -592,6 +592,16 @@ describe('<QueryBuilder />', () => {
  expect(onQueryChange.mock.calls[2][0].rules[0].operator).toBe('!=');
  });
  + it('should change the combinator of the root group', () => {
  + expect(wrapper.find(RuleGroup)).toHaveLength(1);
  + expect(onQueryChange.mock.calls[0][0].rules).toHaveLength(0);
  +
  + wrapper.find('select.ruleGroup-combinators').simulate('change', { target: { value: 'or' } });
  +
  + expect(onQueryChange.mock.calls[1][0].rules).toHaveLength(0);
  + expect(onQueryChange.mock.calls[1][0].combinator).toBe('or');
  + });
  +
  it('should set default value for a rule', () => {
  wrapper.setProps({
  fields,
  