Test had not been updated since version 3.

  - copy paste and adapt code of hpp::core::ConnectedComponent.

  - RoadmapNode::symbolicComponent -> RoadmapNode::leafConnectedComponent,
  - Roadmap::symbolicComponents -> Roadmap::leafConnectedComponents.
  - rename private member Roadmap::symbolicCCs_ -> leafCCs_,
  - rename private member RoadmapNode::symbolicCC_ -> leafCC_.

In class Roadmap call parent implementation in init method

  - parent implementation initializes weak_ member.

Update to changes into hpp::core::pathOptimization::SplineGradientBased