bug #19061 [FORM] fix post_max_size_message translation (alt. 2) (David Badura)

This PR was merged into the 2.7 branch.

Discussion
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[FORM] fix post_max_size_message translation (alt. 2)

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #15479, #18543
| License       | MIT
| Doc PR        | -

Commits
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9d8a5e5 fix post_max_size_message translation

Author: fabpot

Resources/config/form.xml

@@ -189,5 +189,10 @@
         <service id="form.type_extension.submit.validator" class="Symfony\Component\Form\Extension\Validator\Type\SubmitTypeValidatorExtension">
             <tag name="form.type_extension" alias="submit" />
         </service>
+        <service id="form.type_extension.upload.validator" class="Symfony\Component\Form\Extension\Validator\Type\UploadValidatorExtension">
+            <tag name="form.type_extension" alias="form" />
+            <argument type="service" id="translator"/>
+            <argument type="string">%validator.translation_domain%</argument>
+        </service>
     </services>
 </container>