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• When I update fleet, the fleet update gameserver using rolling update strategy. I'd like to see the flow of change in gameserverset.
• agones_fleets_replicas_count metric only has fleet_name

Describe the solution you'd like
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• Add metric agones_gameserverset_replicas_count for gameserverset.
  • This will be useful for checking the progress of the update

Additional context
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• https://agones.dev/site/docs/guides/metrics/