Bump 3rdparty/broker from 3dc3aef to 2169dd8

Bumps [3rdparty/broker](https://github.com/zeek/broker) from `3dc3aef` to `2169dd8`.
- [Release notes](https://github.com/zeek/broker/releases)
- [Commits](zeek/broker@3dc3aef...2169dd8)

---
updated-dependencies:
- dependency-name: 3rdparty/broker
  dependency-type: direct:production
...

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