Implicit cast from Boolean to UInt8

[sundy-li]

Summary: make some functions work with boolean datatypes.

So we can transform avg(boolean) ---> avg(uint8)

---

Now databend boolean return true/false , like this:

[local] [sql]> select 1>0, 0>1;
[ok] ✅ Query precheck passed!
+---------+---------+
| (1 > 0) | (0 > 1) |
+---------+---------+
| true    | false   |
+---------+---------+
[ok] ✅ read rows: 1, read bytes: 1 B, rows/sec: 500 (rows/sec), bytes/sec: 500 (B/sec), time: 0.002 sec

if we can make boolean return 0/ 1 like this:

[local] [sql]> select 1>0, 0>1;
[ok] ✅ Query precheck passed!
+---------+---------+
| (1 > 0) | (0 > 1) |
+---------+---------+
| 1       | 0        |
+---------+---------+
[ok] ✅ read rows: 1, read bytes: 1 B, rows/sec: 500 (rows/sec), bytes/sec: 500 (B/sec), time: 0.002 sec

if support boolean return 0 or 1 , can optimize sql :
The percentage of delays by carrier for 2007

SELECT Carrier, c, c2, c*100/c2 as c3
FROM
(
    SELECT
        IATA_CODE_Reporting_Airline AS Carrier,
        count(*) AS c
    FROM ontime
    WHERE DepDelay>10
        AND Year=2007
    GROUP BY Carrier
) q
JOIN
(
    SELECT
        IATA_CODE_Reporting_Airline AS Carrier,
        count(*) AS c2
    FROM ontime
    WHERE Year=2007
    GROUP BY Carrier
) qq USING Carrier
ORDER BY c3 DESC;

Better version of the same query:

SELECT IATA_CODE_Reporting_Airline AS Carrier, avg(DepDelay>10)*100 AS c3
FROM ontime
WHERE Year=2007
GROUP BY Carrier
ORDER BY c3 DESC

Originally posted by @wubx in #3267

[BohuTANG]

Fixed in #4237