Bump protobuf from 4.21.12 to 4.25.8 in /playground/infrastructure (#35320)

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 4.21.12 to 4.25.8.
- [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/commits/v4.25.8)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-version: 4.25.8
  dependency-type: direct:production
...

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Author: dependabot[bot]

playground/infrastructure/requirements.txt

@@ -24,7 +24,7 @@ tqdm~=4.62.3
 sonora==0.2.2
 pydantic==1.10.13
 grpcio-tools==1.62.1
-protobuf==4.21.12
+protobuf==4.25.8
 google-cloud-datastore==2.11.0
 
 requests~=2.28.2