docs(loader): implement and document vars and attrs

[lalithkarikelli]

Description

<hx-loader> : Implement and Document attributes and variables

What are the relevant story cards/tickets? Any additional PRs or other references?

Jira: SURF2112

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• For UI changes, did you manually test in recent versions of modern browsers (Chrome, Firefox, and Safari)?
• For UI changes, did you manually test in IE11 and legacy Edge?
• Did you add component tests for any new code?
• Did you run the component unit tests via yarn test to ensure all tests passed?
• Did you include a screenshot of the component tests?
• If you changed/added functionality, did you update the demo page and documentation?
• If needed, did you add or modify the demo test page to test the changed/added functionality?
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• In Jira, have you linked to this PR on the ticket(s)?

[netlify]

Deploy preview for helix-ui ready!

Built with commit 85bab9d

https://deploy-preview-829--helix-ui.netlify.app

[100stacks]

@lalithkarikelli, please check and verify these updates work in IE11 and Legacy Edge along with Firefox, Safari, and Chrome.

[lalithkarikelli]

@lalithkarikelli, please check and verify these updates work in IE11 and Legacy Edge along with Firefox, Safari, and Chrome.

@100stacks i have checked and updated the code to work in all 5 browsers. Please review.

[badejayayesubabu]

DEV LGTM

[100stacks]

Dev LGTM