Add support for dcgmExporter specific annotations

[leolimas]

We need to apply Datadog annotations specifically to the DCGM Exporter DaemonSet.

Currently, setting annotations via the daemonsets block applies them to all components, which clutters the configuration of other DaemonSets where these annotations are not needed.

To address this, I am proposing to add a dedicated annotations block to the dcgmExporter section. This provides a more granular configuration method and keeps other components clean.

Datadog annotations:

[maciej-tatarski]

I see 2 PRs open for this feature:

• Feature: Allow setting annotations exclusively on dcgmExporter #1717
• Add pod labels and annotations for DCGM Exporter #1554

Could somebody take a look on them?