validate if date is valid before updating the value to prevent invali…

…d dates sent to the server, fixes ST-255

resources/js/Components/Common/DatePicker.vue

@@ -18,7 +18,7 @@ function updateDate(event: Event) {
     const target = event.target as HTMLInputElement;
     const newValue = target.value;
     const newDate = getDayJsInstance()(newValue);
-    if (newDate) {
+    if (newDate.isValid()) {
         model.value = getLocalizedDayJs(model.value)
             .set('year', newDate.year())
             .set('month', newDate.month())