Bump chisel3 from `e4878e17` to `6a943006` (#182)

Bumps [chisel3](https://github.com/freechipsproject/chisel3) from `e4878e17` to `6a943006`.
- [Release notes](https://github.com/freechipsproject/chisel3/releases)
- [Commits](https://github.com/freechipsproject/chisel3/compare/e4878e17f6a0f309201666d14baedd41f8978e8a...6a943006144c0561daaae28a717440d4a835564c

)

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

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>