feat: add prettier workflow

[Abdel-Monaam-Aouini]

Requirements

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

Related issues

Provide links to any issues in this repository or elsewhere relating to this pull request.

Describe the solution you've provided

Provide a clear and concise description of what you expect to happen.

Describe alternatives you've considered

Provide a clear and concise description of any alternative solutions or features you've considered.

Additional context

Add any other context about the pull request here.

[yusinto]

We are internally restructuring this repo and have enforced our own code formatting standards. As such we won't be accepting this pr at this time. Thank you for your contributions.

[kinyoklion]

Per previous comments closing this PR. Thank you for the contribution, but new code will be developed in the js-core repository.

The equivalent of this package is here: https://github.com/launchdarkly/js-core/tree/main/packages/shared/sdk-client