update lesson labels to not display when completed

src/main/java/seedu/address/model/student/Lesson.java

@@ -146,6 +146,6 @@ public int hashCode() {
      * Format state as text for viewing.
      */
     public String toString() {
-        return '[' + value + ']';
+        return this.subject + "  " + this.date.toString() + "  " + this.time;
     }
 }

src/main/java/seedu/address/ui/StudentCard.java

@@ -61,6 +61,7 @@
         remark.setText(student.getRemark().value);
         student.getLessons().stream()
                 .sorted(Comparator.comparing(Lesson::getLessonValue))
-                .forEach(lesson -> lessons.getChildren().add(new Label(lesson.getLessonValue())));
+                .filter(x -> x.getLessonStatus() == 0)
+                .forEach(lesson -> lessons.getChildren().add(new Label(lesson.toString())));
     }
 }