Set sane default timeout for BasicHost.NewStream

[MarcoPolo]

BasicHost.NewStream takes a context, but if that context is Background, it may block indefinitely. While it's better for the caller to set some timeout that makes sense in their context, we can do better than blocking forever.

Also see: libp2p/go-libp2p-kad-dht#994

Note: we tried to fix this here: https://github.com/libp2p/go-libp2p/pull/2907/files. But this is still an issue when we negotiate MSS:

go-libp2p/p2p/host/basic/basic_host.go

Lines 730 to 747 in 921cc71

	// Negotiate the protocol in the background, obeying the context.
	var selected protocol.ID
	errCh := make(chan error, 1)
	go func() {
	selected, err = msmux.SelectOneOf(pids, s)
	errCh <- err
	}()
	select {
	case err = <-errCh:
	if err != nil {
	return nil, fmt.Errorf("failed to negotiate protocol: %w", err)
	}
	case <-ctx.Done():
	s.Reset()
	// wait for `SelectOneOf` to error out because of resetting the stream.
	<-errCh
	return nil, fmt.Errorf("failed to negotiate protocol: %w", ctx.Err())
	}

.