Missing tests on media-auth and collaboration-auth views

[sampaccoud]

Problem

This PR could be modified without any test breaking: https://github.com/suitenumerique/docs/pull/556/files#diff-cc27a5de6f1d8131250e4be30d0fd4c2f1a816bdc35951a9c86e6f13cd795019

This shows that we are missing some tests.

Proposed solution

Investigate and add missing tests.