removing extraneous brackets in quiz

3-terrarium/1-intro-to-html/.github/pre-lecture-quiz.md

@@ -4,16 +4,16 @@ Complete this quiz in class
 
 1. HTML stands for 'HyperText Mockup Language'
 
-- [ ] [true]
+- [ ] true
-- [ ] [false]
+- [ ] false
 
 2. All HTML tags need both opening and closing tags
 
-- [ ] [true]
+- [ ] true
-- [ ] [false]
+- [ ] false
 
 3. Using semantic markup is most important for 
 
-- [ ] [code readability]
+- [ ] code readability
-- [ ] [screen readers]
+- [ ] screen readers
-- [ ] [maintenance]
+- [ ] maintenance