Bump chisel3 from 6229113 to 8b8b9a3

Bumps [chisel3](https://github.com/chipsalliance/chisel3) from `6229113` to `8b8b9a3`.
- [Release notes](https://github.com/chipsalliance/chisel3/releases)
- [Commits](chipsalliance/chisel@6229113...8b8b9a3)

---
updated-dependencies:
- dependency-name: chisel3
  dependency-type: direct:production
...

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