Add Scheduled Data Import Script for Groups Population in CMDB Classes

[KUSHAL1912]

PR Description:

This PR introduces a new scheduled data import script under
Server-Side Components/scheduled-jobs/Scheduled Data Import for Groups Population (Support and Managed By) for CMDB Classes
to automate the population of Support Group and Managed By Group fields for CMDB classes during data imports.

⚙️ Files Added

post-script.js — Contains the GlideRecord logic that:

Iterates through import set records for a specified CMDB class.

Identifies the corresponding backend CMDB table.

Retrieves Support Group and Managed By Group sys_ids from sys_user_group.

Updates the relevant CI records accordingly.

README.md — Explains the script purpose, usage instructions

Pull Request Checklist

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[snamjosh]

Looks good to me.