Support parse "tablename.struct(xxxxx)" to be Expr::Struct

[Lordworms]

related to apache/datafusion#9891

[Lordworms]

how to reproduce

select struct(time,load1,load2,host) from t1;

r#"SELECT t1."struct(time,load1,load2,host)" FROM t1;"#;

[Lordworms]

I think there are two ways to solve the problem, the first one is to separate the struct in Tokenizer, like in

we could try to match "struct" here and if it matches, do the same logic as the non-quote "match".
The second one is to do a rewrite in Datafusion, but it also includes the parse of "t1."struct(xxxxx)", but we have to deal with I think the best way to do it is in SQL-parser.
However, the tricky part is how to determine the pattern of parse quoted "struct(xxx)", since the tokenizer's next() method does not have a state to save the previous token(my current thought is when the last token is Period and the dialect is a general or big query, we do the logics above). I don't know whether it is the best way. Could you please give me a hint about it? @alamb