[FEATURE] Support annotations on Grafana dashboard #427

Is your feature request related to a problem? Please describe.
I'm trying to organize my dashboards by folders, but I can't put version-checker dashboards in a folder as the ConfigMap does not support adding annotations

Describe the solution you'd like
Support adding annotations for the Grafana dashboards resources

Describe alternatives you've considered
I don't think this applies

Additional context
You create a folder and add your dashboards using the grafana_folder annotation

annotations:
    grafana_folder: $FOLDER_NAME

Message from the maintainers:

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