Update github passport strategy

[MortenHofft]

Apparently the passport library we use for Github is not up to date with how Github prefer auth. We should update the library or find an alternative if updating is not an option.

Hello there!

On February 4th, 2020 at 08:20 (UTC) your application (GBIF.org) used an access token (with the User-Agent passport-github) as part of a query parameter to access an endpoint through the GitHub API.

https://api.github.com/user/emails

Please use the Authorization HTTP header instead as using the `access_token` query parameter is deprecated.

Depending on your API usage, we'll be sending you this email reminder once every 3 days for each token and User-Agent used in API calls made on your behalf.
Just one URL that was accessed with a token and User-Agent combination will be listed in the email reminder, not all.

Visit https://developer.github.com/changes/2019-11-05-deprecated-passwords-and-authorizations-api/#authenticating-using-query-parameters for more information.

Thanks,
The GitHub Team

[thomasstjerne]

jaredhanson/passport-github#75

[thomasstjerne]

Should be fixed by c11d413 , if not -> re-open