[framework] Annotations fixer access of nullable does not break fixer…

… (#3357)

Co-authored-by: Milan Staňo <milan.stano@shopsys.com>

src/Component/ClassExtension/MethodAnnotationsFactory.php

@@ -129,7 +129,7 @@ protected function isMethodImplementedInClass(string $methodName, ReflectionClas
         try {
             $reflectionMethod = $reflectionClass->getMethod($methodName);
 
-            return $reflectionMethod->getDeclaringClass()->getName() === $reflectionClass->getName();
+            return $reflectionMethod?->getDeclaringClass()->getName() === $reflectionClass->getName();
         } catch (OutOfBoundsException $ex) {
             return false;
         }