MDL-11825 - Force penaltyfactor to 1 for truefalse questions on GIFT …

…import, as is done on the editing form. Merged from MOODLE_18_STABLE.

question/format/gift/format.php

@@ -380,6 +380,7 @@ function readquestion($lines) {
                     $question->feedbacktrue = $feedback['wrong'];
                 }
 
+                $question->penalty = 1;
                 $question->correctanswer = $question->answer;
 
                 return $question;