CPU usage is misreported.

Currently "0 CPU" means "no CPU metric received in the previous ProfileEvents packet". But there can be many ProfileEvents packets and only a few with CPU increment.

That's why the CPU metric shows something weird like:
```
0
0
0
0
0
1234
0
0
0
...
```

This is unbearable, and the CPU metric should be either fixed or removed altogether.
const char *& this_query_begin, const char *& th const char * all_queries_end,
    String & query_to_execute, ASTPtr & parsed_query, const String & all_queries_text,
    std::unique_ptr<Exception> & current_exception)
{
    if (!is_interactive && cancelled)
        return MultiQueryProcessingStage::QUERIES_END;
    if (this_query_begin >= all_queries_end)
        return MultiQueryProcessingStage::QUERIES_END;
    // Remove leading empty newlines and other whitespace, because they
    // are annoying to filter in query log. This is mostly relevant for
    // the tests.
    while (this_query_ueries_end && isWhitespaceASCII(*this_query_begin))
        ++this_query_begin;
    if (this_query_begin >= all_queries_end)
        return MultiQueryProcessingStage::QUERIES_END;
    // If there are only comments left ul the end of file, we just
    // stop. The parser can't handle this situation because it always
    // expects that there is some query that it can parse.
    // We can get into this situation because the parser also doesn't
    // skip the trailing comments after parsing a query. This is because
    // they may as well be the leading comments for the next query,