Bump riscv-tests from `a6ab6ae` to `394937e`

Bumps [riscv-tests](https://github.com/riscv/riscv-tests) from `a6ab6ae` to `394937e`.
- [Release notes](https://github.com/riscv/riscv-tests/releases)
- [Commits](https://github.com/riscv/riscv-tests/compare/a6ab6ae6008ffc2ea907ea9f6d2b8379583e7d56...394937eceb62bc4ba8ad5a4e916f0508d9803229

)

---
updated-dependencies:
- dependency-name: riscv-tests
  dependency-type: direct:production
...

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