error_tracking_sum missing from UsageBillableSummaryKeys

[jSherz]

Is your feature request related to a problem? Please describe.
The API returns the error tracking billing information in the error_tracking_sum field, but this is not automatically unmarshalled / parsed by the Datadog SDK.

Describe the solution you'd like
The response returned by datadogV1.UsageMeteringApi.GetUsageBillableSummary supports all fields returned by the Datadog API.

Describe alternatives you've considered
We can workaround this with the AdditionalProperties field, but it's a bit manual/messy.

Additional context
API documentation: https://docs.datadoghq.com/api/latest/usage-metering/#get-monthly-cost-attribution

[github-actions]

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[jSherz]

The file in question has not been updated in 5 months - this is still valid.

[github-actions]

Thanks for your contribution!

This issue has been automatically marked as stale because it has not had activity in the last 30 days. Note that the issue will not be automatically closed, but this notification will remind us to investigate why there's been inactivity. Thank you for participating in the Datadog open source community.

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[jSherz]

Still no update - the file (https://github.com/DataDog/datadog-api-client-go/blob/master/api/datadogV1/api_usage_metering.go) is unchanged.

[github-actions]

Thanks for your contribution!

This issue has been automatically marked as stale because it has not had activity in the last 30 days. Note that the issue will not be automatically closed, but this notification will remind us to investigate why there's been inactivity. Thank you for participating in the Datadog open source community.

If you would like this issue to remain open:

1. Verify that you can still reproduce the issue in the latest version of this project.

2. Comment that the issue is still reproducible and include updated details requested in the issue template.

[jSherz]

Still not fixed.