feat(feature-detector): introduces findGlobals() utility

[feugy]

📖 What's in there?

Second (out of 3) part of the feature detector: returning a list of globals used in a given file.

• feat(feature-detector): introduces findGlobals() which returns the list of globals.

All global variables, that is, identifiers that are not considered as ES2019 builtins and Edge-runtime globals (AbortController, Request, Response...) will be reported.

🧪 How to test?

Besides unit tests, there's an documented example:

Here is a test file. It's in JavaScript, but TypeScript is supported as well.
1. build the repo `pnpm build`
1. make a test file
```js
// test.js
if (typeof process !== 'undefined') {
  console.log('in node', __dirname)
} else if (typeof window !== 'undefined') {
  console.log('in a browser', document)
}
setTimeout(() => console.log('setTimeout is not a global, nor console'), 0)

2. open the node REPL (same folder):

const { findGlobals } = require('./packages/feature-detector/dist')
> undefined
findGlobals('./test.js')
> ['process', '__dirname', 'window', 'document']

Notes to reviewers

We don't need patch-type-definition script any more. The previous solution was pulling to many type definition: we must not load the full DOM types because many of them are not supported in the edge runtime.
If we do, TS compiler will not consider window to be a global, for example.
I couldn't find a way to reuse @edge-runtime/types or @edge-runtime/primitives: they have too much adherence with Node.js types, and it bringing too much for the global detection.
This is documented in the type-definition.txt file.

I made a unit test to detect globals in axios. There's a new script to build the test fixture, so axios is bundled as will the user code be. This script should only run manually, when someone needs to change the fixture.

I'm very sorry about this, but I had to disable turbo cache for build scripts. We're getting poisoned built artifacts which are constantly failing the tests.

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Name	Status	Preview	Comments	Updated
edge-runtime	✅ Ready (Inspect)	Visit Preview	💬 Add your feedback	Jan 18, 2023 at 5:14PM (UTC)

[changeset-bot]

🦋 Changeset detected

Latest commit: 353d9a4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@edge-runtime/feature-detector	Minor

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[nuta]

LGTM 👍 Nice work!