Regression: Decreased tolerance to column names matching SQL keywords

[sergiimk]

Related to: apache/datafusion#17802

Between versions 0.57.0 and 0.58.0 there appears to be a regression that decreased parser tolerance to column names that collide with SQL keywords.

Example:

use sqlparser::dialect::GenericDialect;
use sqlparser::parser::Parser;

fn main() {
    let dialect = GenericDialect {}; // or AnsiDialect

    let sql = r#"
        SELECT
            'a' as a,
            offset
        FROM my_table
    "#;

    let ast = Parser::parse_sql(&dialect, sql).unwrap();
    println!("AST: {:#?}", ast);
}

This works on version 0.57.0, but fails on 0.58.0 with error:

ParserError("Expected: end of statement, found: my_table at Line: 5, Column: 14")

These queries work fine, which adds some confusing inconsistency into the mix:

SELECT
    offset
FROM my_table

SELECT
    offset,
    'a' as a
FROM my_table