Merge pull request #12707 from systimotic/fix/intro-image-centering

Center images in introduction challenges

common/app/routes/challenges/components/step/Step.jsx

@@ -191,6 +191,7 @@ export class StepChallenge extends PureComponent {
           >
           <Image
             alt={ imgAlt }
+            className='center-block'
             responsive={ true }
             src={ imgUrl }
           />