Update containerd to 2f69be5594.

Signed-off-by: Lantao Liu <lantaol@google.com>

vendor/golang.org/x/net/websocket/websocket.go

@@ -241,7 +241,10 @@ func (ws *Conn) Close() error {
 	return err1
 }
 
+// IsClientConn reports whether ws is a client-side connection.
 func (ws *Conn) IsClientConn() bool { return ws.request == nil }
+
+// IsServerConn reports whether ws is a server-side connection.
 func (ws *Conn) IsServerConn() bool { return ws.request != nil }
 
 // LocalAddr returns the WebSocket Origin for the connection for client, or