Update MySqlConnector.php (#13930)

Sometimes we don't need  to set names and collate.

src/Illuminate/Database/Connectors/MySqlConnector.php

@@ -30,13 +30,14 @@ public function connect(array $config)
         // Next we will set the "names" and "collation" on the clients connections so
         // a correct character set will be used by this client. The collation also
         // is set on the server but needs to be set here on this client objects.
-        $charset = $config['charset'];
+        if (isset($config['charset'])) {
+            $charset = $config['charset'];
 
-        $names = "set names '$charset'".
-            (! is_null($collation) ? " collate '$collation'" : '');
-
-        $connection->prepare($names)->execute();
+            $names = "set names '$charset'".
+                (! is_null($collation) ? " collate '$collation'" : '');
 
+            $connection->prepare($names)->execute();
+        }
         // Next, we will check to see if a timezone has been specified in this config
         // and if it has we will issue a statement to modify the timezone with the
         // database. Setting this DB timezone is an optional configuration item.