CI: (deps): Bump protobuf from 5.29.3 to 6.31.1 in /ci

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 5.29.3 to 6.31.1.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](protocolbuffers/protobuf@v5.29.3...v6.31.1)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-version: 6.31.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

ci/requirements.txt

@@ -1,5 +1,5 @@
 beautifulsoup4==4.13.4
 numpy==2.2.4
 pandas==2.3.0
-protobuf==5.29.3
+protobuf==6.31.1
 requests==2.32.4