feat(sinks): Loki Sink supports setting requests of persistent connection

[tiantangkuohai]

Summary

Implement #22022

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.

Notes

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    • cargo fmt --all
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References

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