Bump riscv-isa-sim from `f45f726` to `ec3c935`

Bumps [riscv-isa-sim](https://github.com/riscv/riscv-isa-sim) from `f45f726` to `ec3c935`.
- [Release notes](https://github.com/riscv/riscv-isa-sim/releases)
- [Commits](https://github.com/riscv/riscv-isa-sim/compare/f45f7269b71e3da218a1e1bb4d08b8954cab2d70...ec3c9357ec58bdd2522eef3d7768b9276ab96b0c

)

---
updated-dependencies:
- dependency-name: riscv-isa-sim
  dependency-type: direct:production
...

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