Translations update from Weblate (#2850)

Co-authored-by: Eric <spice2wolf@gmail.com>
Co-authored-by: Allan Nordhøy <epost@anotheragency.no>
Co-authored-by: J. Lavoie <j.lavoie@net-c.ca>
Co-authored-by: Yaron Shahrabani <sh.yaron@gmail.com>
Co-authored-by: Wellington Terumi Uemura <wellingtonuemura@gmail.com>
Co-authored-by: Anders Johansson <johansson@aljmedia.se>
Co-authored-by: Oğuz Ersen <oguzersen@protonmail.com>
Co-authored-by: Roman Shabanov <romash2605@gmail.com>
Co-authored-by: Simona Iacob <s@zp1.net>
Co-authored-by: Milo Ivir <mail@milotype.de>
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Co-authored-by: SC <lalocas@protonmail.com>
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translations/validators.fr.xlf

@@ -66,6 +66,18 @@
         <source>An equal username is already used.</source>
         <target>Un nom d'utilisateur identique est déjà utilisé.</target>
       </trans-unit>
+      <trans-unit id="An activity needs to be selected.">
+        <source>An activity needs to be selected.</source>
+        <target>Une activité doit être sélectionnée.</target>
+      </trans-unit>
+      <trans-unit id="This timesheet is already exported.">
+        <source>This timesheet is already exported.</source>
+        <target>Cette feuille d'heures est déjà exportée.</target>
+      </trans-unit>
+      <trans-unit id="A project needs to be selected.">
+        <source>A project needs to be selected.</source>
+        <target>Un projet doit être sélectionné.</target>
+      </trans-unit>
     </body>
   </file>
 </xliff>