Correct error around Active Sessions

Author: AutomatedTester

webdriver-spec.html

@@ -1295,7 +1295,7 @@ <h2>Sessions</h2>
  <a href=https://html.spec.whatwg.org/#top-level-browsing-context>top-level browsing context</a>.
 
 <p>A <a>remote end</a> has an associated list of
- <dfn data-lt="active session|active sessions">active sessions</dfn>,
+ <dfn data-lt="active sessions|active session">active sessions</dfn>,
  which is a list of all <a>sessions</a> that are currently started.
 
 <p>Requests, except <a>New Session</a> requests,