Replace node-fetch with node-fetch-native

[kidonng]

• Tests pass
• Appropriate changes to README are included in PR
• Types updated

I'm aware this task is already assigned to others, but here I'm proposing it as a bug fix for Deno targeting zx v7. node-fetch seems to cause a infinite loop in Deno:

import 'npm:zx/globals'

fetch('https://example.com') // Infinite loop!

So why node-fetch-native? To sum its readme up:

• Use native fetch when available (thus doesn't break Deno)
• Smaller installation size
• Works with outdated Node version

Thus I consider it a good alternative to removing node-fetch entirely in v8.

This change does introduce a small issue: if TypeScript users have outdated @types/node then RequestInfo and RequestInit types will be missing. I assume this is rare if they are using TypeScript anyway.

[antongolub]

Resolved in #722