add override in Task

I very much considered just removing the protected inheritance again,
but it would add unnecessary code duplication.

Take note, the overriding `insert` function bypasses the Wrapper and directly forwards to the wrapped container.
This is somewhat dirty and could be an issue for anyone inheriting from `Task`.

Author: v4hn

core/include/moveit/task_constructor/task.h

@@ -82,7 +82,7 @@ class Task : protected WrapperBase
 	     ContainerBase::pointer&& container = std::make_unique<SerialContainer>("task pipeline"));
 	Task(Task&& other);
 	Task& operator=(Task&& other);
-	~Task();
+	~Task() override;
 
 	const std::string& id() const;
 
@@ -93,7 +93,7 @@ class Task : protected WrapperBase
 	void loadRobotModel(const std::string& robot_description = "robot_description");
 
 	void add(Stage::pointer&& stage);
-	bool insert(Stage::pointer&& stage, int before = -1);
+	bool insert(Stage::pointer&& stage, int before = -1) override;
 	void clear() final;
 
 	/// enable introspection publishing for use with rviz