Added missing use statement for InvalidOptionsException

Author: neoshadybeat

Form/Type/DatePickerType.php

@@ -10,6 +10,7 @@
 use Symfony\Component\Form\FormView;
 use Symfony\Component\Form\ReversedTransformer;
 use Symfony\Component\OptionsResolver\OptionsResolverInterface;
+use Symfony\Component\OptionsResolver\Exception\InvalidOptionsException;
 
 /**
  * See `Resources/doc/date-picker/overview.md` for documentation