build(deps): Bump external/benchmark from 3d88aff to b2b0aab

Bumps [external/benchmark](https://github.com/google/benchmark) from `3d88aff` to `b2b0aab`.
- [Release notes](https://github.com/google/benchmark/releases)
- [Commits](google/benchmark@3d88aff...b2b0aab)

---
updated-dependencies:
- dependency-name: external/benchmark
  dependency-type: direct:production
...

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