Bump protobuf from 5.28.3 to 5.29.5 in /requirements

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 5.28.3 to 5.29.5.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](protocolbuffers/protobuf@v5.28.3...v5.29.5)

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

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

Author: dependabot[bot]

requirements/test.txt

@@ -743,7 +743,7 @@ propcache==0.2.0
     #   yarl
 proto-plus==1.26.1
     # via google-api-core
-protobuf==5.28.3
+protobuf==5.29.5
     # via
     #   google-api-core
     #   googleapis-common-protos