Add 'export' class to definition terms to be referenced in the Digital Credentials API (#1945)

Author: mohamedamir

index.html

@@ -292,7 +292,7 @@ <h2>Nodes</h2>
   a specific <a>intermediary node</a> and an <a>endpoint node</a> are
   said to be <dfn>upstream</dfn> of the <a>endpoint node</a>.
 
- <dt><dfn>Endpoint node</dfn>
+ <dt><dfn class="export">Endpoint node</dfn>
  <dd>An endpoint node is the final <a>remote end</a>
   in a chain of nodes that is not an <a>intermediary node</a>.
   The endpoint node is implemented by a user agent or a similar program.
@@ -1819,7 +1819,7 @@ <h3>Processing capabilities</h3>
  <li><p>Return <a>success</a> with data <a><code>null</code></a>.
 </ol>
 
-<p>When required to <dfn>validate capabilities</dfn> with
+<p>When required to <dfn class="export">validate capabilities</dfn> with
  argument <var>capabilities</var>:
 
 <ol>
@@ -1964,7 +1964,7 @@ <h3>Processing capabilities</h3>
 </aside>
 
 <p>
- When <dfn>matching capabilities</dfn> given
+ When <dfn class="export">matching capabilities</dfn> given
  JSON <a>Object</a> <var>capabilities</var>, and a <a>session
  configuration flags</a> <var>flags</var>, an <a>endpoint node</a>
  must take the following steps: