Follow-up: Upgrade live-2 OpenSearch Cluster

[FolarinOyenuga]

Background

As a follow-up to the Downscale live-2 OpenSearch cluster, this ticket is geared towards bumping the current version to a more recent one. This will form the finishing part of the previous ticket's goal (which was only scoped to downscaling the cluster).
Had a chat with Jazz regarding this and he suggested that it be handled in a separate ticket (which this is). I have had a look through open tickets in backlog but found none that's specific to this.

NOTE: The current version is 1.3 in live-2, while the current target upgrade version via the dashboard is 2.19

Approach

• Test upgrade via clickOps in a test OS cluster to upgrade to the current version live currently uses.
• Then go on to upgrade live-2 if everything checks out without issues via terraform

Which part of the user docs does this impact

Communicate changes

• post for #cloud-platform-update
• Weeknotes item
• Show the Thing/P&A All Hands/User CoP
• Announcements channel

Questions / Assumptions

Definition of done

• readme has been updated
• user docs have been updated
• another team member has reviewed
• smoke tests are green
• prepare demo for the team

Reference

How to write good user stories