message: change single instance provider back to the way it was
  there was no changes to it, so there was no need for it.
diff: */
  import parseGitUrl from 'git-url-parse';
  -
  +import { GithubAppConfig, GitHubIntegrationConfig } from './config';
  +import { createAppAuth } from '@octokit/auth-app';
  +import { Octokit, RestEndpointMethodTypes } from '@octokit/rest';
  +import { DateTime } from 'luxon';
  import {
  GithubCredentials,
  GithubCredentialsProvider,
  GithubCredentialType,
  } from './types';
  -import { GithubAppConfig, GitHubIntegrationConfig } from './config';
  -import { Octokit, RestEndpointMethodTypes } from '@octokit/rest';
  -import { createAppAuth } from '@octokit/auth-app';
  -import { DateTime } from 'luxon';
  -
  -/**
  - * This accept header is required when calling App APIs in GitHub Enterprise.
  - * It has no effect on calls to github.com and can probably be removed entirely
  - * once GitHub Apps is out of preview.
  - */
  -const HEADERS = {
  - Accept: 'application/vnd.github.machine-man-preview+json',
  -};
  -
  type InstallationData = {
  installationId: number;
  suspended: boolean;
  @@ -66,6 +55,15 @@ class Cache {
  date.diff(DateTime.local(), 'minutes').minutes > 50;
  }
  +/**
  + * This accept header is required when calling App APIs in GitHub Enterprise.
  + * It has no effect on calls to github.com and can probably be removed entirely
  + * once GitHub Apps is out of preview.
  + */
  +const HEADERS = {
  + Accept: 'application/vnd.github.machine-man-preview+json',
  +};
  +
  /**
  * GithubAppManager issues and caches tokens for a specific GitHub App.
  */
  