Feat: make lamassu-migrate use async local storage

lib/async-storage.js

@@ -1,11 +1,10 @@
 const { AsyncLocalStorage } = require('async_hooks')
 const asyncLocalStorage = new AsyncLocalStorage()
 
-const defaultStore = (a = null) => {
+const defaultStore = () => {
   const store = new Map()
   store.set('schema', 'public')
   store.set('defaultSchema', 'ERROR_SCHEMA')
-  if (a) store.set('a', 'a')
   return store
 }