Just replace PH flag with ConfigCat flag for edge functions index error
rates
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Refactor**
* Switched how the feature flag for edge functions request metrics is
read, affecting whether last-hour metrics columns are displayed.
* **Bug Fix**
* Fixed table layout so the "No results found" row correctly spans the
appropriate number of columns depending on whether last-hour stats are
shown, preventing misaligned table rows and improving display
consistency.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Joshen Lim <joshenlimek@gmail.com>
