Update IcalFieldsWizard.php to prevent WSOD
Change to (new class {use SmartDateTrait;}
resolves the original "Deprecated function" error.
Change to is_object($dateRrule)
resolves a new error that appears after the first one is resolved:
Error: Call to a member function getAssembledRule() on null in Drupal\views_ical\Plugin\views\row\IcalFieldsWizard->addSmartDateEvent() (line 511 of modules/contrib/views_ical/src/Plugin/views/row/IcalFieldsWizard.php).