Fix phpstan

src/Monolog/SignalHandler.php

@@ -80,6 +80,7 @@ class SignalHandler
      */
     public function handleSignal(int $signo, $siginfo = null): void
     {
+        /** @var array<int, string> $signals */
         static $signals = [];
 
         if (!$signals && extension_loaded('pcntl')) {