fix tests on mssql

no json_extract

Author: lovasoa

tests/sql_test_files/it_works_fetch_with_meta_error.sql

@@ -2,6 +2,6 @@ set res = sqlpage.fetch_with_meta('http://not-a-real-url');
 
 select 'text' as component,
     case
-        when json_extract($res, '$.error') LIKE '%Request failed%' then 'It works !'
+        when $res LIKE '%"error":"Request failed%' then 'It works !'
         else CONCAT('Error! Got: ', $res)
     end as contents;