[patch] Need to install the MongoDB via GitOps/ArgoCD

[golviya1712]

MASAIB-2891

Changes

• Added changes to render the MongoDB database configuration in the gitops-env repository.
• Automated the MongoDB role as part of the SaaS flow, as we are planning to automate SLS installation with the MongoDB role for AI Service.
• Added the gitops_mongo_database function to render the required YAML file in the gitops-env repository.
• Added the required MongoDB parameters at the cluster level.
• Tested the changes in the SaaS cluster for AI Service. Screenshots are attached for reference.

Evidences:

[whitfiea]

I think this should really be part of the existing gitops_mongo function and is just a new provider https://github.com/ibm-mas/cli/blob/master/image/cli/mascli/functions/gitops_mongo rather than a distinct new function.

Also the gitops PR needs to be linked that will act on these new values being set.