build(deps): bump third_party/sby from fa5d5ad to 26b3874

Bumps [third_party/sby](https://github.com/YosysHQ/sby) from `fa5d5ad` to `26b3874`.
- [Commits](YosysHQ/sby@fa5d5ad...26b3874)

---
updated-dependencies:
- dependency-name: third_party/sby
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>