fix(openapi): method OpenApi::getComponents may return null

Author: vincentchalamon

src/OpenApi/OpenApi.php

@@ -50,7 +50,7 @@ public function getPaths(): Paths
         return $this->paths;
     }
 
-    public function getComponents(): Components
+    public function getComponents(): ?Components
     {
         return $this->components;
     }