feat: support datadog Autodiscovery v2 api annotation

[ericsyh]

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[ignacioli]

The metrics with the _total subfix are counter-type. https://github.com/DataDog/integrations-core/blob/master/openmetrics/datadog_checks/openmetrics/data/conf.yaml.example#L97-L101

Note: To collect counter metrics with names ending in _total, specify the metric name without the _total
suffix. For example, to collect the counter metric promhttp_metric_handler_requests_total, specify
promhttp_metric_handler_requests. This submits to Datadog the metric name appended with .count`.

[ericsyh]

fixed in 76359e3

[ignacioli]

Note: To collect counter metrics with names ending in _total, specify the metric name without the _total
suffix. For example, to collect the counter metric promhttp_metric_handler_requests_total, specify
promhttp_metric_handler_requests. This submits to Datadog the metric name appended with .count.

[ericsyh]

fixed in 76359e3

[ericsyh]

@ignacioli updated based on your comment, pls help take a look again.

[ignacioli]

Seems the metric override configs should be put in metadata. annotations.ad.datadoghq.com/prometheus-example.checks. instances[metrics]. AD Annotations v2 doesn’t support type_overrides for now. see https://docs.datadoghq.com/containers/kubernetes/prometheus/?tab=kubernetesadv2#metric-collection-with-prometheus-annotations

[ignacioli]

LGTM