docs: add CHANGELOG entry for dompurify upgrade

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Co-authored-by: linear-code[bot] <222613912+linear-code[bot]@users.noreply.github.com>

Author: brendan-kellam

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 - Upgraded `@grpc/grpc-js` to `^1.14.4`. [#1315](https://github.com/sourcebot-dev/sourcebot/pull/1315)
 - Upgraded `vite` to `^8.0.16`. [#1313](https://github.com/sourcebot-dev/sourcebot/pull/1313)
+- Upgraded `dompurify` to `^3.4.11`. [#1329](https://github.com/sourcebot-dev/sourcebot/pull/1329)
 
 ## [5.0.3] - 2026-06-17