grpc_function_handle_destruct - Destructs a function handle.
  grpc_error_t grpc_function_handle_destruct(grpc_function_handle_t *handle)
  grpc_function_handle_t *handleThe grpc_function_handle_destruct() function destructs a function handle.
This function is MT-safe.
If successful, GRPC_NO_ERROR is returned. In the case of an error, Error code is returned.
  GRPC_NOT_INITIALIZED  GRPC_INVALID_FUNCTION_HANDLE  GRPC_TIMEOUT_NP  GRPC_OTHER_ERROR_CODE