minor #53200 Added missing Serbian (sr_Cyrl) translation (bojanadamovic)

This PR was merged into the 5.4 branch.

Discussion
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Added missing Serbian (sr_Cyrl) translation

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | Fix #53042
| License       | MIT

Added missing Serbian (sr_Cyrl) translation

Commits
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c94798e5ed Added missing Serbian (sr_Cyrl) translation

Author: nicolas-grekas

Resources/translations/validators.sr_Cyrl.xlf

@@ -426,6 +426,10 @@
                 <source>Using hidden overlay characters is not allowed.</source>
                 <target>Коришћење скривених преклопних карактера није дозвољено.</target>
             </trans-unit>
+            <trans-unit id="110">
+                <source>The extension of the file is invalid ({{ extension }}). Allowed extensions are {{ extensions }}.</source>
+                <target>Екстензија фајла није валидна ({{ extension }}). Дозвољене екстензије су {{ extensions }}.</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>