Fix remaining CI/CD issues

- Add yoast/phpunit-polyfills ^2.0 to composer.json for WordPress test suite compatibility
- Define WP_TESTS_PHPUNIT_POLYFILLS_PATH in bootstrap.php before loading WP test framework
- Update actions/cache to v4 (deprecated SHA references cause failures)
- Update actions/setup-java to v4
- Update codacy/codacy-analysis-cli-action to v4 tag (SHA ref not found)
- Update github/codeql-action/upload-sarif to v3

composer.json

@@ -16,6 +16,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^9.5.0",
+        "yoast/phpunit-polyfills": "^2.0",
         "10up/wp_mock": "^1.0",
         "dealerdirect/phpcodesniffer-composer-installer": "^1.0",
         "wp-coding-standards/wpcs": "^3.0",