Do not check for class that is always available

Author: sebastianbergmann

src/Framework/TestRunner.php

@@ -11,7 +11,6 @@
 
 use const PHP_EOL;
 use function assert;
-use function class_exists;
 use function defined;
 use function error_clear_last;
 use function extension_loaded;
@@ -386,12 +385,6 @@ private function canTimeLimitBeEnforced(): bool
             return $this->timeLimitCanBeEnforced;
         }
 
-        if (!class_exists(Invoker::class)) {
-            $this->timeLimitCanBeEnforced = false;
-
-            return $this->timeLimitCanBeEnforced;
-        }
-
         $this->timeLimitCanBeEnforced = (new Invoker)->canInvokeWithTimeout();
 
         return $this->timeLimitCanBeEnforced;