fix: Grafana sync times are blank for longer time ranges

[adityapk00]

Change Summary

• Fix grafana formula

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PR-Codex overview

This PR focuses on fixing an issue in Grafana where sync times are blank for longer timeranges.

Detailed summary:

• Changed lineInterpolation from "stepBefore" to "smooth"
• Changed target value from "stats.timers.hubble.syncengine.sync_time_ms.mean" to "stats.timers.hubble.syncengine.sync_time_ms.sum"

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[changeset-bot]

🦋 Changeset detected

Latest commit: b125903

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@farcaster/hubble	Patch

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Name	Status	Preview	Comments	Updated (UTC)
hub-monorepo	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 13, 2023 5:42pm

[codecov]

Codecov Report

Patch has no changes to coverable lines.

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