[Postgres]: `?` JSON operator cannot be parsed without a space after the field name

[lukapeschke]

When using PostgreSqlDialect, the question mark cannot be parsed if it is not followed by a space, whereas postgres accepts the query. The following code panics when parsing broken:

fn main() {
    let broken = r#"SELECT user?'adress' FROM my_table"#;
    let working = r#"SELECT user? 'adress' FROM my_table"#;

    let working_parsed =
        sqlparser::parser::Parser::parse_sql(&sqlparser::dialect::PostgreSqlDialect {}, working)
            .expect("Failed to parse SQL query");
    println!("{:?}", working_parsed);

    let broken_parsed =
        sqlparser::parser::Parser::parse_sql(&sqlparser::dialect::PostgreSqlDialect {}, broken)
            .expect("Failed to parse SQL query");
    println!("{:?}", broken_parsed);
}