test 5.1: license is 'cancel' state, register ko but test fails

[llemeurfr]

Test on a license that is in 'cancel' state (b2.lcpl). The EDRLab license server returns a 403 (forbidden) on 'register'. But the test "Check that a 'register' request returns an error" fails; it should be OK.

[RemiBauzac]

@llemeurfr,

In the spec (https://readium.github.io/technical/readium-lsd-specification/), the return codes of register must be:

• 200 on OK
• 400 on Your device could not be registered properly.
• 500 on An unexpected error has occurred.

The test check if the return code is 400. The server has to return this code.