`INTERVAL '1 hour'` should be equivalent to `INTERVAL 1 HOUR`

**Use case**
People are used to Postgres.
{
        return operator_parser.parse(pos, node, expected);
    }
};
class ParserLogicalAndExpression : public IParserBase
{
private:
    ParserVariableArityOperatorList operator_parser {"AND", "and", std::make_unique<ParserLogicalNotExpression>()};
protected:
    const char * getName() const override { return "logical-AND expression"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override
    {
        return operator_parser.parse(pos, node, expected);
    }
};
class ParserLogicalOrExpression : public IParserBase
{
private:
    ParserVariableArityOperatorList operator_parser {"OR", "or", std::make_unique<ParserLogicalAndExpression>()};
protected:
    const char * getName() const override { return "logical-OR expression"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override
    {
        return operator_parser.parse(pos, node, expected);
    }
};
/** An expression with ternary operator.
  * For example, a = 1 ? b + 1 : c * 2.
  */
class ParserTernaryOperatorExpression : public IParserBase