Provider access token

[Dksie09]

What does this PR do?

Updates GitHub OAuth doc by adding a provider access token section

Test Plan

Doc updates

Related PRs and Issues

(If this PR is related to any other PR or resolves any issue or related to any issue link all related PR and issues here.)

Have you read the Contributing Guidelines on issues?

yes

[gewenyu99]

@Dksie09 Thanks for adding these responses, did you get a chance to sanity check the code examples by running them quickly?