fix: [AA-1078] weekly learning goals a11y nav (#711)

- Add radio role and aria-checked to button to enable screen reader use

src/course-home/outline-tab/widgets/FlagButton.jsx

@@ -14,9 +14,8 @@ function FlagButton({
       type="button"
       className={classnames('flag-button m-1.5 pt-3 pb-md-3 pb-xl-0',
         isSelected ? 'flag-button-selected' : '')}
-      // aria-checked={isSelected}
-      // role="radio"
-      // tabIndex={isSelected ? '0' : '-1'}
+      aria-checked={isSelected}
+      role="radio"
       onClick={() => handleSelect()}
       data-testid={`weekly-learning-goal-input-${title}`}
     >

src/course-home/outline-tab/widgets/WeeklyLearningGoalCard.jsx

@@ -64,10 +64,6 @@ function WeeklyLearningGoalCard({
           </Card.Text>
           <div
             className="flag-button-container m-0 p-0"
-              // making this work as a radio button for keyboard nav
-              // is not working
-              // role="radiogroup"
-              // aria-labelledby="learning_goal_choices_label"
           >
             <LearningGoalButton
               level="casual"