Update changelogs from fern repo (#5002)

Co-authored-by: dsinghvi <10870189+dsinghvi@users.noreply.github.com>

Author: fern-support

fern/products/sdks/generators/php/changelog/2026-04-20.mdx

@@ -0,0 +1,10 @@
+## 2.4.2
+**`(chore):`** Bump phpunit/phpunit dev dependency from 9.0 to 12.5.22 to address
+GHSA-qrr6-mg7r-m243 (argument injection via newline in PHP INI values
+forwarded to child processes). Also bumps the PHP version used by the
+generated `ci.yml` workflow from 8.1 to 8.3, which is the minimum
+supported by PHPUnit 12. The `php` constraint in generated
+`composer.json` files is unchanged at 8.1, so production installs
+(`composer install --no-dev`) are unaffected.
+
+