Replace check for uniqueness of checked sections in MDPuqi

src/Checks/Puqi/MDPuqi.php

@@ -1110,16 +1110,16 @@ public function markSectionChecked(MDPuqiCheckSection $section):void {
      */
     public function validateChecksCompleteness():void {
 
-        if (array_unique($this->_checkedSections) !== $this->_checkedSections) {
-            throw new Exception("A section has been checked twice");
-        }
-
         foreach (MDPuqiCheckSection::cases() as $case) {
             if (!in_array($case, $this->_checkedSections, true)) {
                 throw new Exception("Section " . $case->name . " was not checked");
             }
         }
 
+        if (count(MDPuqiCheckSection::cases()) < count($this->_checkedSections)) {
+            throw new Exception("A section has been checked twice");
+        }
+
     }
 
     /**