add types, nodenext, upgrade mime

[Uzlopak]

It will also upgrade the mime package.

In fastify-static we would need to change this block

https://github.com/fastify/fastify-static/blob/8dab6ec5c4525cbe132ec1b7863d884392288406/index.js#L449

to

function getContentType (path) {
  const type = send.mime.getType(path)
 
  if (!send.isUtf8Mimetype(type)) {
    return type
  }
  return `${type}; charset=UTF-8`
}

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[coveralls]

Pull Request Test Coverage Report for Build 3899987296

• 10 of 11 (90.91%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.3%) to 98.408%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
index.js	10	11	90.91%

Totals
Change from base Build 3891979112:	-0.3%
Covered Lines:	390
Relevant Lines:	391

---

💛 - Coveralls

[mcollina]

lgtm