Fix keys filter method

Author: ggrachdev

module/ggrachdev.debugbar/classes/general/BitrixDebugger/Debugger/FilterDebugger.php

@@ -65,7 +65,7 @@ public function last(): self {
         return $this;
     }
 
-    public function keys(array $availableKeys): self {
+    public function keys(array $availableKeys = []): self {
         $this->getFiltrator()->addFilter('keys', [
             'keys' => $availableKeys
         ]);