Update index.html

Co-authored-by: Dave Longley <[email protected]>

Author: jandrieu

index.html

@@ -734,7 +734,7 @@ <h3>BitstringStatusListEntry</h3>
         </p>
 
         <p class="note">
-It is important to note that the statusListIndex is the only link between
+It is important to note that `statusListIndex` is the only link between
 the [=Verifiable credential=] and its status in the list. The
 ```credentialSubject.id``` is not used when checking status. 
         </p>