Update date-draft and draft fields in validator-libraries-modern.yml for the C++ jsoncons implementation

[danielaparker]

What kind of change does this PR introduce?

Update to entry for jsoncons implementation in validator-libraries-modern.yml

Issue Number:

• Closes #___
• Related to #___
• Others?

Screenshots/videos:

If relevant, did you update the documentation?

Summary

Update date-draft and draft fields in validator-libraries-modern.yml for the C++ jsoncons implementation

Does this PR introduce a breaking change?

No breaking change

[github-actions]

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[github-actions]

Welcome to the JSON Schema Community. Thanks a lot for creating your first pull request!! 🎉🎉 We are so excited you are here! We hope this is only the first of many! For more details check out README.md file.

[benjagm]

Thanks a lot for updating the information @danielaparker !!!