build(deps): bump diff in /webgui-new

Bumps  and [diff](https://github.com/kpdecker/jsdiff). These dependencies needed to be updated together.

Updates `diff` from 5.2.0 to 5.2.2
- [Changelog](https://github.com/kpdecker/jsdiff/blob/master/release-notes.md)
- [Commits](kpdecker/jsdiff@v5.2.0...v5.2.2)

Updates `diff` from 4.0.2 to 4.0.4
- [Changelog](https://github.com/kpdecker/jsdiff/blob/master/release-notes.md)
- [Commits](kpdecker/jsdiff@v5.2.0...v5.2.2)

---
updated-dependencies:
- dependency-name: diff
  dependency-version: 5.2.2
  dependency-type: indirect
- dependency-name: diff
  dependency-version: 4.0.4
  dependency-type: indirect
...

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Author: dependabot[bot]