Bump third-party/verilator/master from 2c74765 to b4d064d (#870)

Bumps [third-party/verilator/master](https://github.com/verilator/verilator) from `2c74765` to `b4d064d`.
- [Commits](verilator/verilator@2c74765...b4d064d)

---
updated-dependencies:
- dependency-name: third-party/verilator/master
  dependency-version: b4d064d1669cc2a8d921eae64f88f4586042c825
  dependency-type: direct:production
...

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Author: dependabot[bot]