Bump 3rd_party/pybind11 from 9ec1128 to 2b2e4ca

Bumps [3rd_party/pybind11](https://github.com/pybind/pybind11) from `9ec1128` to `2b2e4ca`.
- [Release notes](https://github.com/pybind/pybind11/releases)
- [Commits](pybind/pybind11@9ec1128...2b2e4ca)

---
updated-dependencies:
- dependency-name: 3rd_party/pybind11
  dependency-type: direct:production
...

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