a11y- Scrollable table is missing role="region"

[katiegoines]

Description of changes:

[Issue]
There are tables present in the below the mentioned sections where they lacks a role region information. Screen reader users will have difficulty determining the purpose and state of these controls.

• Add caption to tables functionality
• In MDXTable, add role="region" to the ScrollView
• use aria-labelledby on the scrollview container to reference the caption element. - there isn't a way to add a prop for caption content so I used the heading the table falls under

staging: https://a11y-scrollable-table.d1egzztxsxq9xz.amplifyapp.com/react/start/migrate-to-gen2/

Ran accessibility tests after changing a page with tables and the tests passed with the role='region' added, which had failed here and why we rolled back this PR

Related GitHub issue #, if available:

Instructions

If this PR should not be merged upon approval for any reason, please submit as a DRAFT

Which product(s) are affected by this PR (if applicable)?

• amplify-cli
• amplify-ui
• amplify-studio
• amplify-hosting
• amplify-libraries

Which platform(s) are affected by this PR (if applicable)?

• JS
• Swift
• Android
• Flutter
• React Native

Please add the product(s)/platform(s) affected to the PR title

Checks

• Does this PR conform to the styleguide?

• Does this PR include filetypes other than markdown or images? Please add or update unit tests accordingly.

• Are any files being deleted with this PR? If so, have the needed redirects been created?

• Are all links in MDX files using the MDX link syntax rather than HTML link syntax?
  
  ref: MDX: [link](https://docs.amplify.aws/)
  HTML: <a href="https://docs.amplify.aws/">link</a>

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• Ready to merge

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[Modernleadershippizza]

Thanks for the quick FIX @katiegoines