message: Fix tests after rebase on serde
diff: @@ -255,9 +255,7 @@ mod test {
  #[test]
  fn parse_err_conversion() {
  - let err = from_slice::<String>(b"123")
  - .context(ParseErr { kind: "String" })
  - .map(|_| ());
  + let err = from_slice::<String>(b"123").map(|_| ());
  assert_conversion(err);
  }
  