PHP-SDK - 4.0.3

• [FSSDK-12316] [Security] Fix curl|bash vulnerability in SourceClear scan by @Tamara-Barum in https://github.com/optimizely/php-sdk/pull/294
• [FSSDK-12610] Fix: PHP 8.4 implicit nullable parameter deprecation warnings by @Tamara-Barum in https://github.com/optimizely/php-sdk/pull/296
• [FSSDK-12610] chore: Prepare release 4.0.3 by @Tamara-Barum in https://github.com/optimizely/php-sdk/pull/297

• @Tamara-Barum made their first contribution in https://github.com/optimizely/php-sdk/pull/294

Full Changelog: https://github.com/optimizely/php-sdk/compare/4.0.2...4.0.3