sks: add commands to generate karpenter-related manifests

[ylmrx]

Description

Add a new generate-karpenter-manifests command in the compute/sks context.

It generates the kubernetes resources needed to enable Karpenter on a given cluster.

The code is displayed on the standard output.

Two flags allow to further tweak the command behavior:

• --nodepool (-n): only display the NodePool resource
• --exoscale-nodeclass (-e): only display the ExoscaleNodeClass resource

When no flags are given, both are assumed, thus both resources are displayed.

Checklist

(For exoscale contributors)

• Changelog updated (under Unreleased block, and add the Pull Request #number for each bit you add to the CHANGELOG.md)
• Testing

Testing

The command was extensively tried out on a preprod cluster.

$ ./cli compute sks generate-karpenter-manifests asd136 --zone nowhere
error: switch client zone v3: get zone api endpoint: find zone: "nowhere" not
found in ListZonesResponse: Not Found
$ ./cli compute sks km not-existant         
error: "not-existant" not found in ListSKSClustersResponse: Not Found
$ ./cli compute sks km asd136 ## [1]
---
apiVersion: karpenter.exoscale.com/v1
kind: ExoscaleNodeClass
(...)
---
apiVersion: karpenter.sh/v1
kind: NodePool
(...)
$ ./cli compute sks km asd136 -e            
---
apiVersion: karpenter.exoscale.com/v1
kind: ExoscaleNodeClass
(...)
$ ./cli compute sks km asd136 -n 
---
apiVersion: karpenter.sh/v1
kind: NodePool
(...)
$ ./cli compute sks km asd136 -ne ## (identical to [1])
---
apiVersion: karpenter.exoscale.com/v1
kind: ExoscaleNodeClass
(...)
---
apiVersion: karpenter.sh/v1
kind: NodePool
(...)

[PhilippeChepy]

lgtm

[nerzhul]

i'd call it generate-karpenter-manifests