Fixes #11390

Fixes #11390

* Add initial support for new env config file

* Fix serverless processEnv call when no env is provided

* Add missing await for test method

* Update env config to .env.json and add dotenv loading

* ncc dotenv package

* Update type

* Update with new discussed behavior removing .env.json

* Update hot-reloader createEntrypoints

* Make sure .env is loaded before next.config.js

* Add tests for all separate .env files

* Remove comments

* Add override tests

* Add test for overriding env vars based on local environment

* Add support for .env.test

* Apply suggestions from code review
Co-Authored-By: NJoe Haddad <joe.haddad@zeit.co>

* Use chalk for env loaded message

* Remove constant as it’s not needed

* Update test

* Update errsh, taskr, and CNA template ignores

* Make sure to only consider undefined missing

* Remove old .env ignore

* Update to not populate process.env with loaded env

* Add experimental flag and add loading of global env values
Co-authored-by: NTim Neutkens <timneutkens@me.com>
Co-authored-by: NJoe Haddad <joe.haddad@zeit.co>

* Add Numeric Separator Support for TypeScript

* Check for number in render

* bump mkdirp to 1.0.3, which support promise

* fix mkdirp in spr-cache.ts

* bump fs-extra to 9.0.0

* remove mkdirp