Adding Authorization Developer Docs

[anawishnoff]

What does this PR do?

Adding a new sub-section to the Developer docs that covers authorization. This includes information on Datadog as an OAuth provider, and how data integrations can use OAuth.

Motivation

OAuth for data integrations is a new feature launching at the end of October.

Additional Notes

OAuth for data integrations is currently in beta, so these docs should not be published until the launch date (please sync internally with me if there are any issues with this)

The link checker may fail in GitLab until https://github.com/DataDog/integrations-core/pull/13060 is merged, also remember to update the pull_config_preview.yaml file before merging in this PR!

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Reviewer checklist

• [ ] Review the changed files.
• [ ] Review the URLs listed in the Preview section.
• [ ] Check images for PII
• [ ] Review any mentions of "Contact Datadog support" for internal support documentation.

[github-actions[bot]]

Preview links (active after the build_preview check completes)

New or renamed files

• https://docs-staging.datadoghq.com/anawishnoff/authorization-developer-docs/developers/authorization/
• https://docs-staging.datadoghq.com/anawishnoff/authorization-developer-docs/developers/authorization/oauth2_endpoints
• https://docs-staging.datadoghq.com/anawishnoff/authorization-developer-docs/developers/authorization/oauth2_in_datadog

Modified Files

[cswatt]

Created DOCS-4186 to track review

[anawishnoff]

@bgoldberg122 Just addressed all of your comments, let me know if there's anything else missing here. thank you so much!