Only request user:email scope by default

Reference:

https://docs.github.com/en/developers/apps/building-oauth-apps/scopes-fo...

> It's unclear to me from the documentation -- does this scope still provide access to the email?

It is a bit unclear - let me double-check this.

So the answer here is yes, it does include email... but that begs the question, do we even need the broader scope or just the email?

Below is an example of the response for my account with the user:email scope, and it's more than sufficient for social auth because it includes other public info:

{
  "login": "bradjones1",
  "id": 981966,
  "node_id": "redacted",
  "avatar_url": "https://avatars.githubusercontent.com/u/981966?v=4",
  "gravatar_id": "",
  "url": "https://api.github.com/users/bradjones1",
  "html_url": "https://github.com/bradjones1",
  "followers_url": "https://api.github.com/users/bradjones1/followers",
  "following_url": "https://api.github.com/users/bradjones1/following{/other_user}",
  "gists_url": "https://api.github.com/users/bradjones1/gists{/gist_id}",
  "starred_url": "https://api.github.com/users/bradjones1/starred{/owner}{/repo}",
  "subscriptions_url": "https://api.github.com/users/bradjones1/subscriptions",
  "organizations_url": "https://api.github.com/users/bradjones1/orgs",
  "repos_url": "https://api.github.com/users/bradjones1/repos",
  "events_url": "https://api.github.com/users/bradjones1/events{/privacy}",
  "received_events_url": "https://api.github.com/users/bradjones1/received_events",
  "type": "User",
  "site_admin": false,
  "name": "Brad Jones",
  "company": null,
  "blog": "",
  "location": "USA",
  "email": "brad@bradjones.name",
  "hireable": true,
  "bio": "Web (mostly PHP ecosystem) and DevOps developer.\r\n\r\nCTO at Fruition.",
  "twitter_username": "bradrjones",
  "public_repos": 107,
  "public_gists": 9,
  "followers": 12,
  "following": 15,
  "created_at": "2011-08-15T21:00:22Z",
  "updated_at": "2021-06-25T23:30:11Z"
}