[stubsabot] Bump protobuf to ~=6.30.0

Release: https://pypi.org/pypi/protobuf/6.30.0
Homepage: https://developers.google.com/protocol-buffers/
Repository: https://github.com/protocolbuffers/protobuf
Typeshed stubs: https://github.com/python/typeshed/tree/main/stubs/protobuf

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Author: stubsabot

Diff for: stubs/protobuf/METADATA.toml

@@ -1,5 +1,5 @@
 # Using an exact number in the specifier for scripts/sync_protobuf/google_protobuf.py
-version = "~=5.29.1"
+version = "~=6.30.0"
 upstream_repository = "https://github.com/protocolbuffers/protobuf"
 extra_description = "Partially generated using [mypy-protobuf==3.6.0](https://github.com/nipunn1313/mypy-protobuf/tree/v3.6.0) and libprotoc 28.1 on [protobuf v29.1](https://github.com/protocolbuffers/protobuf/releases/tag/v29.1) (python `protobuf==5.29.1`)."
 partial_stub = true