message: ODBC: return SQL_SUCESS for some connection attr.
diff: @@ -157,9 +157,9 @@ SQLRETURN SQL_API SQLSetConnectAttr(SQLHDBC connection_handle, SQLINTEGER attrib
  case SQL_ATTR_TRACEFILE:
  case SQL_ATTR_TRANSLATE_LIB:
  case SQL_ATTR_TRANSLATE_OPTION:
  - case SQL_ATTR_TXN_ISOLATION:
  - dbc->error_messages.emplace_back("Optional feature not supported.");
  - return SQL_ERROR;
  + case SQL_ATTR_TXN_ISOLATION: {
  + return SQL_SUCCESS;
  + }
  default:
  return SQL_ERROR;
  }
  