Simplify/update Superimpose and ExtractROI tests

Description

OTB tests are old and data is evolving. Most of these tests lack of documentation are the data used is old. We will start to check/document and update OTB test starting with the most used applications.

Definition of Ready

Generic:

• If this issue is consequent, it is split into subtasks with priority and complexity evaluated. These subtasks should be linked to this issue. (To do on GitLab interface after writing this issue)
• Issue complexity evaluated
• Priority of issue evaluated
• If there is specific test data needed, it should be detailed and available
• If there is a specific documentation/specification need, it should be available to the development team
• Time during the sprint to realize this issue
• Blocking elements resolved (check if non-applicable, detail otherwise the resolved elements)

Specific:

• Up-to-date data for theses two application.

Definition of Done

Generic:

• No test regression on CI
• Code reviewed by peers
• Code cleaned, no "debug" traces or "TODO" comments kept.
• New code documented