reduce audio modal heading to h2

bigbluebutton-html5/imports/ui/components/audio/audio-modal/component.jsx

@@ -558,11 +558,11 @@ class AudioModal extends Component {
                 {
                   isIOSChrome ? null
                     : (
-                      <h3 className={styles.title}>
+                      <h2 className={styles.title}>
                         {content
                           ? intl.formatMessage(this.contents[content].title)
                           : intl.formatMessage(intlMessages.audioChoiceLabel)}
-                      </h3>
+                      </h2>
                     )
                 }
               </header>