Re: BUG #16035: STATEMENT_TIMEOUT not working when we have singlequote usage inside CTE which is used in inner sql

If there's no objection, I would like to commit/push the diff.

> I admit v11's current behavior is inconstant, but I am not sue going
> to back V10's behavior is a good idea.
> 
> With attached patch (against master), SET STATEMENT_TIMEOUT
> immediately affects to subsequent commands in the multi statement. I
> think this is not only more intuitive than v10's behavior but it meets
> the original reporter's expectation.
> 
> SET STATEMENT_TIMEOUT = '10s';
> SET
> Time: 0.418 ms
> -- SELECT timeout in 1 second.
> SET STATEMENT_TIMEOUT = '1s'\;SELECT * FROM ( WITH test AS ( SELECT pg_sleep(5), 'Billy' as emp_name ) SELECT 1 FROM
test) AS sub;
 
> ERROR:  canceling statement due to statement timeout
> Time: 1001.107 ms (00:01.001)
> 
> Here are results of test cases attached (statement_timeout.sql).
> 
> \timing
> Timing is on.
> -- SELECT timeout in 1 second.
> SET STATEMENT_TIMEOUT = '1s'\;SELECT * FROM ( WITH test AS ( SELECT pg_sleep(5), 'Billy' as emp_name ) SELECT 1 FROM
test) AS sub;
 
> psql:/home/t-ishii/tmp/statement_timeout.sql:3: ERROR:  canceling statement due to statement timeout
> Time: 1001.138 ms (00:01.001)
> SET STATEMENT_TIMEOUT = '10s';
> SET
> Time: 0.434 ms
> -- SELECT timeout in 1 second.
> SET STATEMENT_TIMEOUT = '1s'\;SELECT * FROM ( WITH test AS ( SELECT pg_sleep(5), 'Billy' as emp_name ) SELECT 1 FROM
test) AS sub;
 
> psql:/home/t-ishii/tmp/statement_timeout.sql:7: ERROR:  canceling statement due to statement timeout
> Time: 1000.978 ms (00:01.001)
> -- This time SELECT succeeds and STATEMENT_TIMEOUT is set to 8 secinds.
> SET STATEMENT_TIMEOUT = '8s'\;SELECT * FROM ( WITH test AS ( SELECT pg_sleep(5), 'Billy' as emp_name ) SELECT 1 FROM
test) AS sub;
 
>  ?column? 
> ----------
>         1
> (1 row)
> 
> Time: 5004.886 ms (00:05.005)
> SHOW STATEMENT_TIMEOUT;
>  statement_timeout 
> -------------------
>  8s
> (1 row)
> 
> Time: 0.433 ms
> -- Following SELECT succeeds because now statement_timeout value is 8 seconds..
> SELECT * FROM ( WITH test AS ( SELECT pg_sleep(5), 'Billy' as emp_name ) SELECT 1 FROM test ) AS sub;
>  ?column? 
> ----------
>         1
> (1 row)
> 
> Time: 5006.196 ms (00:05.006)