[Forwardport] Format the javascript code in Tax module

[gelanivishal]

Original Pull Request

#15343

Description

Refactor javascript validate code in Tax module.

Fixed Issues (if relevant)

1. Reformat the javascript code as per magento standards. #15352: Reformat the javascript code as per magento standards

Manual testing scenarios

N/A

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @vgelani. Thank you for your contribution.
Changes from your Pull Request will be available with the upcoming 2.3.0 release.