Bump protobuf from 3.20.3 to 5.28.3

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 3.20.3 to 5.28.3.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](protocolbuffers/protobuf@v3.20.3...v5.28.3)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

docker_requirements.txt

@@ -18,7 +18,7 @@ OSKut==1.3
 pandas==1.4.*
 panphon==0.20.0
 phunspell==0.1.6
-protobuf==3.20.3
+protobuf==5.28.3
 pyicu==2.8
 python-crfsuite==0.9.11
 requests==2.31.*