POST using repo.save(todo) may replace

[arnobl]

If the user specifies an existing ID during a POST, it will update the existing resource and not create a new one.

[arnobl]

Maybe add a new question after the first POST to discuss this point:

• in swagger set id to 2
• try to add three todo
• the backend does not create a todo with ID 3
• before, repo.save(todo) call todo.setId(-1)