docs: update webrtc example (#2777)

Updates example to incorporate changes from #2776

This is done in a separate PR because doing it in #2776 would cause
a major of `@libp2p/webrtc` to be released.

Author: achingbrain

packages/transport-webrtc/README.md

@@ -97,14 +97,15 @@ const relay = await createLibp2p({
 // WebRTC connections
 const listener = await createLibp2p({
   addresses: {
-  listen: ['/webrtc']
+    listen: [
+      '/p2p-circuit',
+      '/webrtc'
+    ]
   },
   transports: [
     webSockets({filter: filters.all}),
     webRTC(),
-    circuitRelayTransport({
-      discoverRelays: 1
-    })
+    circuitRelayTransport()
   ],
   connectionEncrypters: [noise()],
   streamMuxers: [yamux()],

packages/transport-webrtc/src/index.ts

@@ -74,14 +74,15 @@
  * // WebRTC connections
  * const listener = await createLibp2p({
  *   addresses: {
- *   listen: ['/webrtc']
+ *     listen: [
+ *       '/p2p-circuit',
+ *       '/webrtc'
+ *     ]
  *   },
  *   transports: [
  *     webSockets({filter: filters.all}),
  *     webRTC(),
- *     circuitRelayTransport({
- *       discoverRelays: 1
- *     })
+ *     circuitRelayTransport()
  *   ],
  *   connectionEncrypters: [noise()],
  *   streamMuxers: [yamux()],