Add instructions to enable metrics for caikit tgis

[VedantMahabaleshwarkar]

Issues

• SPIKE: Investigate kserve monitoring and metrics opendatahub-community#70
• [P0] Verify which metrics CAIKit/TGIS produce caikit#3

Description

• Updated caikit-tgis-serving image to the latest one available
• Added optional environment variable in the Serving Runtime that is required to enable CPU only inferencing
• Added instructions and resources needed to enable caikit metrics

How Has This Been Tested?

• Tested a fresh Kserve(ODH deployment) + Serverless + ServiceMesh deployment
• Deployed ServingRuntime and ISVC according to the demo files
• Followed instructions added in the readme
• Verified metrics show up in Openshift Console

Merge criteria:

• The commits are squashed in a cohesive manner and have meaningful messages.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: VedantMahabaleshwarkar, Xaenalt

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [VedantMahabaleshwarkar,Xaenalt]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment