Bump simple-plist from 1.1.0 to 1.3.1 in /frontend

Bumps [simple-plist](https://github.com/wollardj/simple-plist) from 1.1.0 to 1.3.1.
- [Release notes](https://github.com/wollardj/simple-plist/releases)
- [Commits](wollardj/simple-plist@1.1.0...v1.3.1)

---
updated-dependencies:
- dependency-name: simple-plist
  dependency-type: indirect
...

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