Format the javascript code in Tax module

[gelanivishal]

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)

[gelanivishal]

@VladimirZaets Thanks.

[magento-engcom-team]

Hi @vgelani. Thank you for your contribution.
Changes from your Pull Request will be available with the upcoming 2.2.5 release.

Please, consider porting this solution across release lines.
You may use Porting tool to port commits automatically.