Remove invalid connection flag. Emulate prepares is disabled by default.

src/Database/Driver/Sqlserver.php

@@ -74,7 +74,6 @@ class Sqlserver extends Driver
         }
 
         $config['flags'] += [
-            PDO::ATTR_EMULATE_PREPARES => false,
             PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
         ];
 

tests/TestCase/Database/Driver/SqlserverTest.php

@@ -132,7 +132,6 @@ class SqlserverTest extends TestCase
 
         $expected = $config;
         $expected['flags'] += [
-            PDO::ATTR_EMULATE_PREPARES => false,
             PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
             PDO::SQLSRV_ATTR_ENCODING => 'a-language',
         ];
@@ -194,7 +193,6 @@ class SqlserverTest extends TestCase
 
         $expected = $config;
         $expected['flags'] = [
-            PDO::ATTR_EMULATE_PREPARES => false,
             PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
             PDO::SQLSRV_ATTR_ENCODING => 'a-language',
         ];