feat: add API to write OpenTelemetry logs to GreptimeDB

[paomian]

I hereby agree to the terms of the GreptimeDB CLA.

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What's changed and what's your intention?

• add API to write OpenTelemetry logs to GreptimeDB

Checklist

• [ ] I have written the necessary rustdoc comments.
• [ ] I have added the necessary unit tests and integration tests.
• [ ] This PR requires documentation updates.