[ticket/17361] Fix file not deleted when there is an error

PHPBB-17361

phpBB/phpbb/files/filespec_storage.php

@@ -447,6 +447,7 @@ class filespec_storage
 			$fp = fopen($this->filename, 'rb');
 
 			$storage->write($this->destination_file, $fp);
+			$this->file_moved = true;
 		}
 		catch (\phpbb\storage\exception\storage_exception $e)
 		{