Description:
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PDOStatement::getColumnMeta() doesn't return native_type for JSON type columns (i suppose it should be "string"). 


Test script:
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$DB=new PDO('mysql:host=localhost;dbname=test','user','pass');
$DB->exec('CREATE TABLE `test` (`a` JSON)');
$DB->exec("INSERT INTO `test` VALUES('[]')");
$statement=$DB->query('SELECT `a` FROM `test`');
$meta=$statement->getColumnMeta(0);

var_dump(isset($meta['native_type']));

Expected result:
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bool(true)

Actual result:
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bool(false)