minor #43464 [Validator] Add validator missing spanish translation (zakaria-ammoura)

This PR was merged into the 4.4 branch.

Discussion
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[Validator] Add validator missing spanish translation

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | #43457
| License       | MIT
| Doc PR        | N/A
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Commits
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346b7cde9f Add validator missing spanish translation

Author: fabpot

Resources/translations/validators.es.xlf

@@ -390,6 +390,10 @@
                 <source>This value should be a valid expression.</source>
                 <target>Este valor debería ser una expresión válida.</target>
             </trans-unit>
+            <trans-unit id="101">
+                <source>This value is not a valid CSS color.</source>
+                <target>Este valor no es un color CSS válido.</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>