Check to see if the file handler is a resource before trying to call …

…fclose. This was causing a warning and making the CsvTest.php fail

setup/src/Magento/Setup/Module/I18n/Dictionary/Writer/Csv.php

@@ -59,14 +59,18 @@ public function write(Phrase $phrase)
      */
     public function __destructor()
     {
-        fclose($this->_fileHandler);
+        if (is_resource($this->_fileHandler)) {
+            fclose($this->_fileHandler);
+        }
     }
 
     /**
      * Destructor for closing file handler
      */
     public function __destruct()
     {
-        fclose($this->_fileHandler);
+        if (is_resource($this->_fileHandler)) {
+            fclose($this->_fileHandler);
+        }
     }
 }