build(deps): bump protobuf in /regression-tests.recursor-dnssec

build(deps): bump protobuf in /regression-tests.recursor-dnssec

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 5.28.2 to 5.29.5.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](https://github.com/protocolbuffers/protobuf/compare/v5.28.2...v5.29.5)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-version: 5.29.5
  dependency-type: direct:production
...

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