fix the wrong usage of xlog when second parameter is not an array

Author: samuraee

src/Logger.php

@@ -43,10 +43,15 @@ public static function __callStatic($name, $arguments)
             $arguments = [$arguments];
         }
 
-        if (isset($arguments[1])) {
+        // fix the wrong usage of xlog when second parameter is not an array
+        if (!isset($arguments[1])) {
             $arguments[1] = [];
         }
 
+        if(!is_array($arguments[1])){
+            $arguments[1] = [$arguments[1]];
+        }
+
         if (session_status() == PHP_SESSION_NONE) {
             $arguments[1]['sid'] = session_id();
         } else {