minor #30585 [Validator] Add the missing translations for the Arabic (ar) locale (mehdimabrouk)

This PR was submitted for the master branch but it was merged into the 3.4 branch instead (closes #30585).

Discussion
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[Validator] Add the missing translations for the Arabic (ar) locale

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no <!-- don't forget to update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | ?    <!-- please add some, will be required by reviewers -->
| Fixed tickets | none   <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | none <!-- required for new features -->

This pull request is for adding missing translations in validators.ar.xlf.
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Commits
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5df08d67a7 [Validator] Add the missing translations for the Arabic (ar) locale

src/Symfony/Component/Validator/Resources/translations/validators.ar.xlf

@@ -330,6 +330,10 @@
                 <source>This Business Identifier Code (BIC) is not associated with IBAN {{ iban }}.</source>
                 <target>رمز المعرّف نشاط تجاري (BIC) هذا لا يرتبط مع IBAN {{ iban }}.</target>
             </trans-unit>
+            <trans-unit id="86">
+                <source>This value should be valid JSON.</source>
+                <target>هذه القيمة يجب أن تكون صالحة ل JSON.</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>