[Blocked dependency] `sodium-native@4.2.0`

## What
The `sodium-native` dependency is blocked on version `4.2.0` because version `4.2.1` breaks install on node-alpine.

## Context
https://github.com/holepunchto/sodium-native/issues/202

The issue basically boils down to the project not using `node-gyp` for building and instead using their own tool.

It looks like if you add `glibc` in the alpine image it will work.

They are working towards a fix.

Until then we will fix the dependency to version 4.2.0 in `package.json`.