Address PHPStan warning in 'classes/logger/sql.php'.

------ --------------------------------------
Line   classes/logger/sql.php
------ --------------------------------------
4      Property Logger_SQL::$pdo is unused.
------ --------------------------------------

1 files changed, 0 insertions, 2 deletions

diff --git a/classes/logger/sql.php b/classes/logger/sql.php
index 784ebef31..0f6177a5b 100755
--- a/classes/logger/sql.php
+++ b/classes/logger/sql.php
@@ -1,8 +1,6 @@
 <?php
 class Logger_SQL implements Logger_Adapter {
 
-	private $pdo;
-
 	function __construct() {
 		$conn = get_class($this);