Usage example doesn't work because `Noise` class isn't exported

[TimDaub]

https://github.com/ChainSafe/js-libp2p-noise#usage

import {Noise} from "@chainsafe/libp2p-noise"

but this class isn't imported by index.ts:

js-libp2p-noise/src/index.ts

Line 2 in 309ec0f

import { Noise } from './noise.js'