Bump shell-quote from 1.7.2 to 1.8.4 in /site-ui

Bumps [shell-quote](https://github.com/ljharb/shell-quote) from 1.7.2 to 1.8.4.
- [Changelog](https://github.com/ljharb/shell-quote/blob/main/CHANGELOG.md)
- [Commits](ljharb/shell-quote@v1.7.2...v1.8.4)

---
updated-dependencies:
- dependency-name: shell-quote
  dependency-version: 1.8.4
  dependency-type: indirect
...

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Author: dependabot[bot]