QA/Markdown: no duplicate links

Author: jrfnl

README.md

@@ -4,12 +4,14 @@
 
 [![Latest Stable Version](http://poser.pugx.org/phpcsstandards/php_codesniffer/v)](https://github.com/PHPCSStandards/PHP_CodeSniffer/releases)
 [![Validate](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/validate.yml/badge.svg?branch=master)](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/validate.yml)
-[![Test](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/test.yml/badge.svg?branch=master)](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/test.yml)
+[![Test](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/test.yml/badge.svg?branch=master)][GHA-test]
 [![Coverage Status](https://coveralls.io/repos/github/PHPCSStandards/PHP_CodeSniffer/badge.svg?branch=master)](https://coveralls.io/github/PHPCSStandards/PHP_CodeSniffer?branch=master)
 [![License](http://poser.pugx.org/phpcsstandards/php_codesniffer/license)](https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt)
 
 ![Minimum PHP Version](https://img.shields.io/packagist/php-v/squizlabs/php_codesniffer.svg?maxAge=3600)
-[![Tested on PHP 5.4 to 8.3](https://img.shields.io/badge/tested%20on-PHP%205.4%20|%205.5%20|%205.6%20|%207.0%20|%207.1%20|%207.2%20|%207.3%20|%207.4%20|%208.0%20|%208.1%20|%208.2%20|%208.3-brightgreen.svg?maxAge=2419200)](https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/test.yml)
+[![Tested on PHP 5.4 to 8.3](https://img.shields.io/badge/tested%20on-PHP%205.4%20|%205.5%20|%205.6%20|%207.0%20|%207.1%20|%207.2%20|%207.3%20|%207.4%20|%208.0%20|%208.1%20|%208.2%20|%208.3-brightgreen.svg?maxAge=2419200)][GHA-test]
+
+[GHA-test]: https://github.com/PHPCSStandards/PHP_CodeSniffer/actions/workflows/test.yml
 
 </div>