Add multiple catalog items to order guide

[raghavs046]

PR Description:

This code will help admins/ catalog admins to add multiple items to order guide with single click.
This also involves:

1. Creation of variable set in catalog items
2. Rule base creation in order guide
3. Order guide variable creation which are selected in rule base.

Pull Request Checklist

Overview

• Put an x inside of the square brackets to check each item.
• I have read and understood the CONTRIBUTING.md guidelines
• My pull request has a descriptive title that accurately reflects the changes and the description has been filled in above.
• I've included only files relevant to the changes described in the PR title and description
• I've created a new branch in my forked repository for this contribution

Code Quality

• My code is relevant to ServiceNow developers
• My code snippets expand meaningfully on official ServiceNow documentation (if applicable)
• I've disclosed use of ES2021 features (if applicable)
• I've tested my code snippets in a ServiceNow environment (where possible)

Repository Structure Compliance

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  • Core ServiceNow APIs/
  • Server-Side Components/
  • Client-Side Components/
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  • Integration/
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• I've used appropriate sub-categories within the top-level categories
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Documentation

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• My PR does not include changes that fall outside the described scope

[github-actions]

Thank you for your contribution. However, it doesn't comply with our contributing guidelines.

As a reminder, the general requirements (as outlined in the CONTRIBUTING.md file) are the following: follow the folder+subfolder guidelines and include a README.md file explaining what the code snippet does.

Validation errors:

Folder structure violations found:
 - Move 'Modern Development/Add Multiple Catalogs to Order Guide/README.md' under a valid folder hierarchy (Category/Subcategory/Use-Case/your-file). Files directly inside 'Modern Development' or its subcategories are not allowed.
 - Move 'Modern Development/Add Multiple Catalogs to Order Guide/Script Include.js' under a valid folder hierarchy (Category/Subcategory/Use-Case/your-file). Files directly inside 'Modern Development' or its subcategories are not allowed.
 - Move 'Modern Development/Add Multiple Catalogs to Order Guide/UI Action.js' under a valid folder hierarchy (Category/Subcategory/Use-Case/your-file). Files directly inside 'Modern Development' or its subcategories are not allowed.
 - Move 'Modern Development/Add Multiple Catalogs to Order Guide/UI Page.js' under a valid folder hierarchy (Category/Subcategory/Use-Case/your-file). Files directly inside 'Modern Development' or its subcategories are not allowed.

Review your contribution against the guidelines and make the necessary adjustments. Closing this for now. Once you make additional changes, feel free to re-open this Pull Request or create a new one.