fix: reset accept fut in stop (#1082)

Co-authored-by: diegomrsantos <diego@status.im>

libp2p/transports/tcptransport.nim

@@ -190,6 +190,7 @@ method stop*(self: TcpTransport) {.async.} =
     await allFutures(toWait)
 
     self.servers = @[]
+    self.acceptFuts = @[]
 
     trace "Transport stopped"
     untrackCounter(TcpTransportTrackerName)
@@ -221,6 +222,7 @@ method accept*(self: TcpTransport): Future[Connection] {.async.} =
       let observedAddr = MultiAddress.init(transp.remoteAddress).tryGet()
       return await self.connHandler(transp, Opt.some(observedAddr), Direction.In)
     except CancelledError as exc:
+      debug "CancelledError", exc = exc.msg
       transp.close()
       raise exc
     except CatchableError as exc: