[Bug] grpcio not being treated as optional dependency

[cretz]

Describe the bug

METADATA inside of wheel has:

Provides-Extra: grpc
Provides-Extra: opentelemetry
Requires-Dist: grpcio (>=1.48.0,<2.0.0)
Requires-Dist: opentelemetry-api (>=1.11.1,<2.0.0); extra == "opentelemetry"
Requires-Dist: opentelemetry-sdk (>=1.11.1,<2.0.0); extra == "opentelemetry"
Requires-Dist: protobuf (>=4.21,<4.22)
Requires-Dist: python-dateutil (>=2.8.2,<3.0.0); python_version < "3.11"
Requires-Dist: types-protobuf (>=3.20,<3.21)
Requires-Dist: typing-extensions (>=4.2.0,<5.0.0)

Why does grpcio not have an extra listed? I think it's because it doesn't reference the grpcio dependency properly in pyproject.toml (calls it grpc instead).