feat: drop cross-fetch polyfill dep

[ilearnio]

It's better if polyfill will be included on the application level rather than having it included by each similar to this vendor package (each may include different polyfill, which turns into bloated app). In my case "cross-fetch" doesn't make sense because I use @babel/polyfill

[gfx]

+1

It is the application that is responsible for polyfills; libraries should not depend on polyfills.

[jasonkuhrt]

Thanks @ilearnio!

[schickling]

🎉 This PR is included in version 2.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[tw00]

This breaks out of the box support for Node... ☹️

If you still want to use this library with Node.js you have to do something like this:

const fetch = require('node-fetch');

/* global globalThis */
if (!globalThis.fetch) {
  globalThis.fetch = fetch;
}

...maybe something to mention in the docs.

[SimenB]

Ideally it should be possible to pass in a fetch-compliant function rather than having to modify the global environment

[SlothFriend]

Breaking out of the box Node support isn't good. Would be great if either:

1. graphql-request worked natively without dependencies out of the box
2. graphql-request worked out of the box with dependencies
3. At the very least made it VERY clear in the README that a dependency is needed for use in Node

EDIT:
Ah, I see the note that this will be fixed - thank you!