feat: emit peer:identify event after identify completes (#1741)

To monitor when peers complete the identify protocol, emit a
`peer:identify` event with the protocol reply.

This is more reliable than doing an on-demand identify since we can
easily breach per-protocol stream limits for identify.

package.json

@@ -128,7 +128,7 @@
     "@libp2p/interface-connection-manager": "^3.0.0",
     "@libp2p/interface-content-routing": "^2.1.0",
     "@libp2p/interface-keychain": "^2.0.4",
-    "@libp2p/interface-libp2p": "^3.0.0",
+    "@libp2p/interface-libp2p": "^3.1.0",
     "@libp2p/interface-metrics": "^4.0.0",
     "@libp2p/interface-peer-discovery": "^2.0.0",
     "@libp2p/interface-peer-id": "^2.0.1",