message: network-grpc: Removed server::Error::Io
  listen() no longer returns server::Error, and that was the only place
  where the Io variant could occur.
diff: @@ -97,7 +97,6 @@ pub fn listen(
  /// The error type for gRPC server operations.
  #[derive(Debug)]
  pub enum Error {
  - Io(tokio::io::Error),
  Http2Handshake(h2::Error),
  Http2Protocol(h2::Error),
  NewService(h2::Error),
  @@ -105,12 +104,6 @@ pub enum Error {
  Execute,
  }
  -impl From<tokio::io::Error> for Error {
  - fn from(err: tokio::io::Error) -> Self {
  - Error::Io(err)
  - }
  -}
  -
  type H2Error<T> = tower_h2::server::Error<gen::node::server::NodeServer<NodeService<T>>>;
  // Incorporating tower_h2::server::Error would be too cumbersome due to the
  @@ -137,7 +130,6 @@ where
  impl fmt::Display for Error {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  match self {
  - Error::Io(e) => write!(f, "I/O error: {}", e),
  Error::Http2Handshake(e) => write!(f, "HTTP/2 handshake error: {}", e),
  Error::Http2Protocol(e) => write!(f, "HTTP/2 protocol error: {}", e),
  Error::NewService(e) => write!(f, "service creation error: {}", e),
  @@ -150,7 +142,6 @@ impl fmt::Display for Error {
  impl ErrorTrait for Error {
  fn source(&self) -> Option<&(dyn ErrorTrait + 'static)> {
  match self {
  - Error::Io(e) => Some(e),
  Error::Http2Handshake(e) => Some(e),
  Error::Http2Protocol(e) => Some(e),
  Error::NewService(e) => Some(e),
  