Function load_or_fetch_network_config 

pub(crate) async fn load_or_fetch_network_config<P: SequencerPersistence>(
    persistence: &P,
    config_peers: Option<Vec<Url>>,
    validator_config: &ValidatorConfig<SeqTypes>,
    backoff: BackoffParams,
    base_timeout: Duration,
) -> Result<Option<LoadedNetworkConfig>>