[BOP-1509] Changes in migration from MKE 3 page

[RaunakShah]

1. The following information is outdated and needs to be fixed:

• Example output for mkectl version should be:

Version: v4.0.0

• Example output for k0sctl version should be:

version: v0.19.4
commit: a06d3f6

• Example output of sudo k0s kc get nodes should be:

NAME                                           STATUS   ROLES           AGE   VERSION
ip-172-31-111-4.us-west-1.compute.internal     Ready    control-plane   45h   v1.31.2+k0s
ip-172-31-216-253.us-west-1.compute.internal   Ready    <none>          45h   v1.31.2+k0s

2. The following information needs to be added:

• Under Prerequisites: add a step to create an MKE 3 backup by following https://docs.mirantis.com/mke/3.7/ops/disaster-recovery/back-up-mke.html
• Under Troubleshoot Migration: we should state that a failed migration will automatically roll back the cluster to their previous MKE 3 configuration. Also ask customers to collect the upgrade logs from the terminal.
• We need to introduce an additional Notes section (or something similar):
  • Inform users that their swarm workloads will be deleted by the migration process
  • Inform users that their workloads running in MKE 3 will be temporarily unavailable during the migration process
  • The upgrade time will depend on the size of their cluster.
  • Users will need to download new kubeconfigs from k0s after the migration
  • The UCP Controller API will no longer be active/supported. This means that the client bundle for MKE 3 will be invalidated.
  • When the migration is in progress, the terminal will have step-by-step logs about the current state of migration.
  • When the migration is successful, the terminal prints a summary of the process. For example:

Upgrade Summary
---------------

Configuration file
---------------
All MKE 3 TOML settings were successfully converted into MKE 4 YAML settings.

Authentication
---------------
Users found in the MKE3 cluster: 1

All users were migrated to the MKE4 cluster successfully.

Authorization
---------------
Organizations found in the MKE3 cluster: 1
Teams found in the MKE3 cluster: 0

All organizations and teams were translated to aggregated roles in the MKE4 cluster successfully.

Ports
---------------
The following MKE3 ports are no longer used by MKE4 and (unless otherwise needed) may be made unavailable on all nodes: [2377,6444,7946,9055,12376,12378,12379,12380,12381,12382,12383,12384,12385,12386,12387,12388,12389,12391,12392,179,12390,2376,443]

MCR
---------------
MCR may safely be uninstalled

MKE3 Cleanup
---------------
MKE 3.7.15 was uninstalled from the cluster successfully.