Bump pest_derive from 2.7.15 to 2.8.0

Bumps [pest_derive](https://github.com/pest-parser/pest) from 2.7.15 to 2.8.0.
- [Release notes](https://github.com/pest-parser/pest/releases)
- [Commits](pest-parser/pest@v2.7.15...v2.8.0)

---
updated-dependencies:
- dependency-name: pest_derive
  dependency-version: 2.8.0
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]