chore: update CHANGELOG

CHANGELOG.md

@@ -8,7 +8,7 @@
 - **redis**: use LRU cache for series metadata
 - **redis**: fix label_names() function to return all label names if no parameter is specified (now the label name auto-completion in the query editor works again)
 - **redis**: remove deprecated `label_values(metric, label)` function
-- **redis**: fix network error for metrics with many series
+- **redis**: fix network error for metrics with many series (requires PCP v6+)
 - **redis**: update debug logging messages
 - **bpftrace**: disable scrolling beyond last line in query editor
 - **checklist**: fix dashboard link in navigation bar