[Dependabot]: Bump riscv-arch-test from a3b7f0c to 873d16e

Bumps [riscv-arch-test](https://github.com/riscv-non-isa/riscv-arch-test) from `a3b7f0c` to `873d16e`.
- [Release notes](https://github.com/riscv-non-isa/riscv-arch-test/releases)
- [Commits](riscv-non-isa/riscv-arch-test@a3b7f0c...873d16e)

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

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