Optimize final introspection json schema

**Is your feature request related to a problem? Please describe.**

I'm using the below code (from [here](https://formidable.com/open-source/urql/docs/graphcache/schema-awareness/)) because I need an introspection schema in my SPA web app:

```js
import { getIntrospectionQuery } from "graphql";
import fetch from "node-fetch";
import * as fs from "fs";

fetch("http://localhost:3000/graphql", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
variables: {},
query: getIntrospectionQuery({ descriptions: false }),
}),
})
.then((result) => result.json())
.then(({ data }) => {
fs.writeFile("./schema.json", JSON.stringify(data), (err) => {
if (err) {
console.error("Writing failed:", err);
return;
}
console.log("Schema written!");
});
});
```

The amazing team at Urql also created packages for optimization: https://formidable.com/open-source/urql/docs/graphcache/schema-awareness/#optimizing-a-schema.

Using that solution my final schema .json is 35% smaller than the one generated by code-generator. And my final schema is part of the client bundle, so any BIT is important!

**Describe the solution you'd like**

Can we optimize like they did?

**Describe alternatives you've considered**

Maybe using options?

**Additional context**

I can use their solution, but it is very inconvenient especially in CI/CD environments where the GraphQL server is not active and I cannot verify the correct schema.

Generating from `*.graphql` files is amazing!

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Thanks for your amazing work!