session_info: RuntimeDescriptor<
    [index: number],

        | {
            active_validator_indices: number[];
            assignment_keys: FixedSizeBinary<32>[];
            discovery_keys: FixedSizeBinary<32>[];
            dispute_period: number;
            n_cores: number;
            n_delay_tranches: number;
            needed_approvals: number;
            no_show_slots: number;
            random_seed: FixedSizeBinary<32>;
            relay_vrf_modulo_samples: number;
            validator_groups: number[][];
            validators: FixedSizeBinary<32>[];
            zeroth_delay_tranche_width: number;
        }
        | undefined,
>

Get the session info for the given session, if stored.

NOTE: This function is only available since parachain host version 2.