Fixed

• Fixed support for nested gRPC callouts.
  Thanks @andytesti!

• Fixed panic on unknown token_id in on_grpc_receive_initial_metadata
  and on_grpc_receive_trailing_metadata.
  Thanks @erikness-doordash!

• Fixed panic on unexpected failures in get_property.
  Thanks @alexsnaps!

• Fixed panic on unexpected failures in call_foreign_function.
  Reported by @geNAZt.

Added

• Added support for sending error responses with gRPC status codes.
  Thanks @juanmolle!