Function enr_to_discv4_id

pub fn enr_to_discv4_id(enr: &Enr) -> Option<PeerId>

Extracts a [CombinedPublicKey::Secp256k1] from a [discv5::Enr] and converts it to a [PeerId]. Note: conversion from discv5 ID to discv4 ID is not possible.