chore(deps-dev): bump yoast/phpunit-polyfills from 2.0.0 to 3.1.1

Bumps [yoast/phpunit-polyfills](https://github.com/Yoast/PHPUnit-Polyfills) from 2.0.0 to 3.1.1.
- [Release notes](https://github.com/Yoast/PHPUnit-Polyfills/releases)
- [Changelog](https://github.com/Yoast/PHPUnit-Polyfills/blob/3.x/CHANGELOG.md)
- [Commits](Yoast/PHPUnit-Polyfills@2.0.0...3.1.1)

---
updated-dependencies:
- dependency-name: yoast/phpunit-polyfills
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

composer.json

@@ -44,7 +44,7 @@
         "wp-coding-standards/wpcs": "^2.3",
         "squizlabs/php_codesniffer": "^3.7",
         "phpcompatibility/php-compatibility": "^9.3",
-        "yoast/phpunit-polyfills": "^2.0"
+        "yoast/phpunit-polyfills": "^3.1"
     },
     "scripts": {
         "format-fix-exit": "\"vendor/bin/phpcbf-fix-exit-0\" --standard=phpcs.xml --report-summary --report-source -s  --runtime-set testVersion 7.0- ",