Translations update from Weblate (#2781)

Co-authored-by: frooog in raain <sadsatan211@gmail.com>
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translations/validators.it.xlf

@@ -54,6 +54,18 @@
         <source>The entered passwords don't match.</source>
         <target>Le password inserite non corrispondono.</target>
       </trans-unit>
+      <trans-unit id="An equal username is already used.">
+        <source>An equal username is already used.</source>
+        <target>Un nome utente uguale è già usato.</target>
+      </trans-unit>
+      <trans-unit id="An equal email is already used.">
+        <source>An equal email is already used.</source>
+        <target>Un indirizzo e-mail uguale è già usato.</target>
+      </trans-unit>
+      <trans-unit id="At least one team leader must be assigned to the team.">
+        <source>At least one team leader must be assigned to the team.</source>
+        <target>Almeno un caposquadra deve essere assegnato alla squadra.</target>
+      </trans-unit>
     </body>
   </file>
 </xliff>