Enable fine tuning of backoff at shoot level

[himanshu-kun]

What would you like to be added:
Currently autoscaler provides these flags to fine tune the backoff mechanism
We need to expose these on shoot level , also keeping in mind that these flags are available only from k8s v1.25.0 and above
Currently following flags are exposed.

Following upstream PR added these flags kubernetes#3853

Why is this needed:

For better usability of autoscaler

[ashwani2k]

Grooming Decision:

No pull for this feature. Hence iceboxing it for now

[dongyingbo]

What is the relation between those flags and fast backoff from ResourceExhaused feature?

[elankath]

@dongyingbo InitialNodeGroupBackoffDuration opt set via initial-node-group-backoff-duration is the duration of first backoff after a new node failed to start. It is currently set to 5m and not configurable. MaxNodeGroupBackoffDuration opt set via "max-node-group-backoff-duration is the is the maximum backoff duration for a NodeGroup and is set to 30m. And lastly NodeGroupBackoffResetTimeout opt set via node-group-backoff-reset-timeout is unfortunately set to 3h by default and is currently not configurable.

[elankath]

Though this fix will likely expedite CA resolution when capacity is added it will not ameliorate the edge case where fallback to alternate node group when capacity is not added. When there are a large number of NodeGroup's managed by the CA, this can be delayed.