Bump generic-array from 0.12.3 to 0.12.4 in /fuzz/storage-proof (#1438)

Bumps [generic-array](https://github.com/fizyk20/generic-array) from 0.12.3 to 0.12.4.
- [Release notes](https://github.com/fizyk20/generic-array/releases)
- [Changelog](https://github.com/fizyk20/generic-array/blob/0.12.4/CHANGELOG.md)
- [Commits](https://github.com/fizyk20/generic-array/compare/0.12.3...0.12.4

)

---
updated-dependencies:
- dependency-name: generic-array
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>