bug #39659 [Form] keep valid submitted choices when additional choices are submitted (xabbuh)

This PR was merged into the 4.4 branch.

Discussion
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[Form] keep valid submitted choices when additional choices are submitted

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #9738
| License       | MIT
| Doc PR        |

Commits
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85989c3678 keep valid submitted choices when additional choices are submitted

Author: xabbuh

Resources/config/form.xml

@@ -69,6 +69,7 @@
         <service id="form.type.choice" class="Symfony\Component\Form\Extension\Core\Type\ChoiceType">
             <tag name="form.type" />
             <argument type="service" id="form.choice_list_factory"/>
+            <argument type="service" id="translator" on-invalid="ignore" />
         </service>
         <service id="form.type.file" class="Symfony\Component\Form\Extension\Core\Type\FileType" public="true">
             <tag name="form.type" />