[Dependabot]: Bump riscv-arch-test from a7b7cd0 to 5bc8876

Bumps [riscv-arch-test](https://github.com/riscv-non-isa/riscv-arch-test) from `a7b7cd0` to `5bc8876`.
- [Release notes](https://github.com/riscv-non-isa/riscv-arch-test/releases)
- [Commits](riscv-non-isa/riscv-arch-test@a7b7cd0...5bc8876)

---
updated-dependencies:
- dependency-name: riscv-arch-test
  dependency-type: direct:production
...

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