docs(changelog): deduplicate openclaw#67679 entry (openclaw#68439)

PR openclaw#67679 landed a duplicate line under ### Changes in the Unreleased
block in addition to the detailed entry that was already present under
### Fixes. The short ### Changes line (auto-generated from the PR title
during merge) is a duplicate of the same PR's ### Fixes line and also
mis-categorizes a security redaction fix as a feature change.

Remove the duplicate and keep the ### Fixes entry, which is the right
section and carries the descriptive text.

Author: hxy91819

CHANGELOG.md

@@ -7,7 +7,6 @@ Docs: https://docs.openclaw.ai
 ### Changes
 
 - macOS/gateway: add `screen.snapshot` support for macOS app nodes, including runtime plumbing, default macOS allowlisting, and docs for monitor preview flows. (#67954) Thanks @BunsDev.
-- fix: redact credentials in browser.cdpUrl config paths (#67679). Thanks @Ziy1-Tan
 
 ### Fixes