Hey 👋🏻,

I have a question, we are looking to use this module alongside the @octokit/graphql.js.

We work behind a corporate proxy, so we need to be able to pass a proxy to any egress request from within our network.

I see that both this and the @octokit/graphql.js modules use the @octokit/request.js) module to make its requests to the GitHub API.

By taking a look at your code, you seem to be using node-fetch for actually making the HTTP Requests behind the scenes.

Taking a look at node-fetch it does support passing in an agent. When taking a look at your request library, there doesn't seem to be any options, which I would have expected to see here? (maybe?)

We would love to be able to pass in a httpsAgent somewhere?

const { createAppAuth } = require("@octokit/auth-app");
const httpAgent = new http.Agent({ keepAlive: true });
const httpsAgent = new https.Agent({ keepAlive: true });

const auth = createAppAuth({
  id: 1,
  privateKey: "-----BEGIN PRIVATE KEY-----\n...",
  installationId: 123,
  clientId: "1234567890abcdef1234",
  clientSecret: "1234567890abcdef12341234567890abcdef1234"
});

const installationAuthentication = await auth({ 
  type: "installation" ,
  agent: url => url.protocol === 'https:' ? httpsAgent : httpAgent
});

const graphqlWithAuth = graphql.defaults({
  request: {
    hook: auth.hook
    agent: url => url.protocol === 'https:' ? httpsAgent : httpAgent
  }
});

Something like that? It would be great if we could do this in a single place when looking through the octokit modules, it would be great to have a single experience across the @octokit ecosystem 🤔?

Just wanted to put it here and get some of your thoughts on best practice 👍

Thanks for all your help.