TransportManger: Use a builder pattern for the transport manager

[lexnv]

litep2p/src/transport/manager/mod.rs

Lines 259 to 268 in e0b7118

	impl TransportManager {
	/// Create new [`crate::transport::manager::TransportManager`].
	// TODO: don't return handle here
	pub fn new(
	keypair: Keypair,
	supported_transports: HashSet<SupportedTransport>,
	bandwidth_sink: BandwidthSink,
	max_parallel_dials: usize,
	connection_limits_config: limits::ConnectionLimitsConfig,
	) -> (Self, TransportManagerHandle) {