[chore] Remove link from deprecated/removed component ballastextension from CHANGELOG

Signed-off-by: Bogdan Drutu <[email protected]>

Author: bogdandrutu

CHANGELOG.md

@@ -2662,7 +2662,7 @@ This release is marked as "bad" since the metrics pipelines will produce bad dat
 
 - Remove Resize() from pdata slice APIs (#3675)
 - Remove the ballast allocation when `mem-ballast-size-mib` is set in command line (#3626)
-  - Use [`ballast extension`](./extension/ballastextension/README.md) to set memory ballast instead.
+  - Use `ballast extension` to set memory ballast instead.
 - Rename `DoubleDataPoint` to `NumberDataPoint` (#3633)
 - Remove `IntHistogram` (#3676)