Allow subtask to have different node definitions between them

[AndrePatri]

As per title.
For example this should be possible:

zero_velocity_contact_1:
  type: Cartesian
  distal_link: contact_1
  indices: [0, 1, 2]
  cartesian_type: velocity
  nodes: ${range(1, N)}

interaction_contact_1:
  type: VertexForce
  frame: contact_1
  fn_min: 5.0
  enable_fc: false
  friction_coeff: 1.0
  vertex_frames:
    - contact_1
    - 
contact_1:
  type: Contact
  subtask: [interaction_contact_1, zero_velocity_contact_1]```