enhancement(greptiemdb_logs source): add config for greptimedb_logs to add http header

[paomian]

Summary

• add http header config for greptimedb_logs sink

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

How did you test this PR?

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the "no-changelog" label to this PR.

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References

[pront]

Thanks @paomian

[paomian]

@pront Thanks to review. Is there anything else to improve about this pr?