Move arch validation logic outside of OS upgrade script

[ipetrov117]

The suggested implementation introduces the following changes:

1. Removal of the existing OS arch validation that was located in the os-upgrade.sh.tpl script template
2. Rework of the SupportedArchs property of the OperatingSystem release manifest configuration:
   • The property has been moved away from a []string to a []Arch type
   • Validation was added for each Arch entry that it holds expected full arch names - x86_64 and aarch64 have been added as initial possible configurations.
   • Logic that converts arch full names to short names (e.g. amd64, arm64.. etc.) was added.
3. OS arch validation is now done by the upgrade-controller, where:
   • each cluster node is validated against the supported architectures (both full name and short name) that have been defined in the release manifest
   • if a node is not running a supported architecture, the OS upgrade fails and both a condition and error message are printed in the UpgradePlan and upgrade-controller respectively.

Example "Failed" UpgradePlan condition message:

apiVersion: lifecycle.suse.com/v1alpha1
kind: UpgradePlan
..
  name: upgradeplan-sample
  namespace: upgrade-controller-system
..
status:
  conditions:
  - lastTransitionTime: "2024-08-21T09:05:32Z"
    message: Cluster nodes are running unsupported architectures
    reason: Failed
    status: "False"
    type: OSUpgraded

Example error message in the upgrade-controller for the following ReleaseManifest configuration:
ReleaseManifest:

apiVersion: lifecycle.suse.com/v1alpha1
kind: ReleaseManifest
metadata:
  name: releasemanifest-sample
  namespace: upgrade-controller-system
spec:
...
    operatingSystem:
      ...
      supportedArchs:
        - "aarch64"

upgrade-controller error message when running on a x86_64 OS arch:

2024-08-21T09:05:42Z  ERROR Reconciler error  {"controller": "upgradeplan", "controllerGroup": "lifecycle.suse.com", "controllerKind": "UpgradePlan", "UpgradePlan": {"name":"upgradeplan-sample","namespace":"upgrade-controller-system"}, "namespace": "upgrade-controller-system", "name": "upgradeplan-sample", "reconcileID": "208a11db-f2d9-47d8-8048-53a2f67fdd20", "error": "validating cluster node OS architecture: unsuported arch 'amd64' for 'mgmt-cluster-network' node. Supported archs: [aarch64]"}
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler
  /go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:316
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem
  /go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:263
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2.2
  /go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:224

Was tested both for failure and successful use-cases.