GitHub Enterprise Server: context.github.graphql() fails with 406

[gr2m]

Bug Report

Current Behavior

When sending a GraphQL Query before sending any other request in an event handler, Probot sends a request to [GHE_HOST]/api/app/installations/[installation id]/access_tokens instead of [GHE_HOST]/api/v3/app/installations/[installation id]/access_tokens. The GHES instance responds with a 406 error

module.exports = (app) => {
  app.on("push", ({ github }) => {
    await github.graphql(`query { 
      viewer { 
        login
      }
    }`)
  });
};

See ttps://probot-talk.slack.com/archives/C6S4FC8AF/p1603208624022600 /cc @pjbreaux

Environment

• Probot version(s): 10.9.3
• GitHub Enterprise Server

[gr2m]

Here is a test case to reproduce the problem with the underlying @octokit libraries:
https://runkit.com/gr2m/probot-probot-1386

RunKit

RunKit notebooks are interactive javascript playgrounds connected to a complete node environment right in your browser. Every npm module pre-installed.

[gr2m]

You'll have to update your dependency tree in order to get the latest version of @octokit/core (3.1.3). When in doubt, try rm -rf package-lock.json node_modules && npm install