Hello,

I would like to convert the Guix tests in the "tests/" directory to
derivations, in the exact same way as for the system tests in the
"gnu/tests/" directory.

For that, I propose to introduce a new <unit-test> record. This would
allow us to select all the unit tests using the "all-unit-tests"
procedure, and add them to the (gnu ci) module.

This way, we could have a Cuirass specification for the unit tests, as
we already have for the system tests, to spot regressions early on.

Here's a patch that translates the "account.scm" test module to the new
proposed mechanism. If there are no objections, I plan to convert all
the remaining tests.

Thanks,

Mathieu