usage metering consolidate

[davidejones]

What does this PR do?

This PR:

• Removes from the usage metering api nav endpoints by specific products e.g Get hourly usage for lambda
• Adds links to these specific endpoints under a v1 tab in get hourly usage by product family

Motivation

API discussions

Preview

View the v1 and v2 tabs for get hourly usage by product family https://docs-staging.datadoghq.com/david.jones/metric-usage-migrate/api/latest/usage-metering/#get-hourly-usage-by-product-family

Check other endpoints in other places operate as normal.

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.

[davidejones]

Just throwing a do not merge on here for now to give api channel a chance for feedback.