update launchdarkly-js-sdk-common

[wilhelmeek]

Requirements

• [ ] I have added test coverage for new or changed functionality
• [x] I have followed the repository's pull request submission guidelines
• [ ] I have validated my changes against all supported platform versions

Related issues

• https://github.com/launchdarkly/js-sdk-common/releases/tag/5.0.3

Describe the solution you've provided

Updates the common SDK which includes an important type fix to make key values optional. Otherwise users are forced to either @ts-ignore your SDK, or provide empty string keys which crash your SDK on iOS (and potentially Android which I haven't verified)

[wilhelmeek]

Thank you @yusinto 🙏