reorg api rate limits

[davidejones]

What does this PR do?

This PR keeps /api/latest/rate-limits/ and removes /api/v1/rate-limits/ and /api/v2/rate-limits in all langauges. To avoid confusion.

Motivation

To avoid confusion with translations. There was an expectation that a translation file should exist but it was a variant.

Preview

https://docs-staging.datadoghq.com/david.jones/rate-limits/api/latest/rate-limits/

Additional Notes

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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): https://docs-staging.datadoghq.com/david.jones/rate-limits/api/v1/rate-limits/ https://docs-staging.datadoghq.com/david.jones/rate-limits/api/v2/rate-limits/