[API Rest & Admin] Default sorting on GET all causes issues

Expected behaviour : The default sorting on GET all requests should make the request's results usable.

Observed behaviour : Currently, for most of GET all requests, the default sorting is more or less random. This sometimes cause the sorting to change from one page to another, especially when the "size" argument is used, and entities to appear multiple times.

Steps to reproduce :

Have a few thousand le test cases (at least enough to fill a few pages of results)
Use a get all on test cases with size=1000
Check the different pages

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