fix typo that caused record to fail on rest calls

lib/session/call-session.js

@@ -1807,7 +1807,7 @@ class CallSession extends Emitter {
           username: JAMBONZ_RECORD_WS_USERNAME,
           password: JAMBONZ_RECORD_WS_PASSWORD
         },
-        disableBiDirectionalAudio: true,
+        disableBidirectionalAudio: true,
         mixType : 'stereo',
         passDtmf: true
       };