build(deps): update protobuf requirement

Updates the requirements on [protobuf](https://github.com/protocolbuffers/protobuf) to permit the latest version.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Commits](https://github.com/protocolbuffers/protobuf/commits)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-version: 7.34.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

setup.cfg

@@ -39,7 +39,7 @@ install_requires =
     authlib>=1.6.7,<2.0.0
     pydantic>=2.12.0,<3.0.0
     grpcio>=1.59.5,<1.80.0
-    protobuf>=4.21.6,<7.0.0
+    protobuf>=4.21.6,<8.0.0
 python_requires = >=3.10
 
 [options.extras_require]