On-behalf-of token and service account authorization tokens doc

[stephen-crawford]

Description

This PR introduces a new document inside the security plugin's access_control directory. The document added details the basic information for On-behalf-of and Service Account tokens. I reviewed the documentation provided for accuracy from a security standpoint and as a doc bar raiser. Hopefully there should not be many further changes required.

I was not sure how to change the linking correctly but did my best.

Issues Resolved

opensearch-project/security#3290
Fixes #4388

Checklist

• By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and subject to the Developers Certificate of Origin.
  For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[hdhalter]

@Naarcha-AWS - Can you please take this over now that Chris is gone? Thanks.

[hdhalter]

@scrawfor99 - did you close this in favor of #4411?

[stephen-crawford]

@hdhalter, I definitely did not mean to close this... Let me see what I did by accident

Update: should be fixed. Sorry about that looks like my rebase wiped it and I did not notice

[stephen-crawford]

@hdhalter I am not sure what that issue with the style check means :/

[stephen-crawford]

The remaining vale warnings I do not plan to address unless required for the documentation to be merged. It is stuff around the headers having numbers etc.

[kolchfa-aws]

Thank you, @scrawfor99! Left some comments.

[kolchfa-aws]

Also, could you add blank lines after each heading? Thanks!

[stephen-crawford]

I don't see how to ignore the review dog comments that remain. It wants to mess with all the headers etc. but I think they are good

[kolchfa-aws]

Thanks, @scrawfor99! A couple of changes before we can mark this PR done.

[stephen-crawford]

@kolchfa-aws should be all set!

[kolchfa-aws]

Thank you, @scrawfor99!

[peternied]

@kolchfa-aws Can this be merged? What is preventing this, can we get 2.12 items merged in a branch so we know they are commited?

[kolchfa-aws]

@peternied We usually merge right before the release. This is done to prevent merge conflicts when someone is working on the same file for the current/previous versions.

[peternied]

@kolchfa-aws Thanks for the fast response. Your scenario is what branches are built for on Github, they allow collaboration and then a PR is made on 'release' day that pulls in all the PRs on that branch.

• I've filed an proposal to revisit this processes [Meta] Pull requests should be merged when they are approved #6305