fix deprecations: add choices_as_values=true + flip contents of choice in ChoiceType

Form/Type/ChoiceWithOtherType.php

@@ -34,6 +34,7 @@ class ChoiceWithOtherType extends AbstractType
         $options['expanded'] = true;
         // adding a default value for choice
         $options['empty_data'] = null;
+        $options['choices_as_values'] = true;
 
         $builder
             ->add('_other', TextType::class, array('required' => false))

Form/Type/LinkedCustomFieldsType.php

@@ -110,6 +110,7 @@ class LinkedCustomFieldsType extends AbstractType
 
         $options = array_merge($this->options, array(
                 'choice_list' => new SimpleChoiceList($choices),
+                'choices_as_values' => true
             ));
 
         $event->getForm()->getParent()->add($this->choiceName, ChoiceType::class,