Core/Chat: fix RBAC_PERM_COMMANDS_NOTIFY_COMMAND_NOT_FOUND_ERROR for subcommands

Ref #18463
(cherry picked from commit eb376f4b7e)

src/server/game/Chat/Chat.cpp

@@ -293,6 +293,9 @@ bool ChatHandler::ExecuteCommandInTable(std::vector<ChatCommand> const& table, c
         {
             if (!ExecuteCommandInTable(table[i].ChildCommands, text, fullcmd))
             {
+                if (m_session && !m_session->HasPermission(rbac::RBAC_PERM_COMMANDS_NOTIFY_COMMAND_NOT_FOUND_ERROR))
+                    return false;
+
                 if (text[0] != '\0')
                     SendSysMessage(LANG_NO_SUBCMD);
                 else