dfn fixes

Co-authored-by: Dominique Hazael-Massieux <[email protected]>

Author: fippo

index.bs

@@ -510,6 +510,7 @@ dictionary RTCEncodedAudioFrameMetadata {
     </dd>
     <dt>
         <dfn dict-member>contributingSources</dfn> <span class=
+        <dfn dict-member>contributingSources</dfn> of type <span class=
             "idlMemberType">sequence&lt;unsigned long&gt;</span>
     </dt>
     <dd>