Code review comment for ~sylvain-pineau/checkbox-ng:fix-1766766

The merge was fine but running tests failed.

[trusty] starting container
[trusty] (timing) 0.01user 0.01system 0:00.28elapsed 9%CPU (0avgtext+0avgdata 4984maxresident)k
[trusty] (timing) 0inputs+72outputs (0major+1433minor)pagefaults 0swaps
[trusty] provisioning container
[trusty] (timing) 68.48user 207.74system 9:45.87elapsed 47%CPU (0avgtext+0avgdata 68500maxresident)k
[trusty] (timing) 105640inputs+1491240outputs (48major+1301260minor)pagefaults 0swaps
[trusty-testing] Starting tests...
Found a test script: ./requirements/001-container-tests-plainbox-egg-info
[trusty-testing] 001-container-tests-plainbox-egg-info: PASS
[trusty-testing] (timing) 0.22user 0.03system 0:00.37elapsed 68%CPU (0avgtext+0avgdata 24396maxresident)k
[trusty-testing] (timing) 224inputs+88outputs (1major+9375minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-checkbox-documentation
[trusty-testing] container-tests-checkbox-documentation: PASS
[trusty-testing] (timing) 0.03user 0.01system 0:00.07elapsed 58%CPU (0avgtext+0avgdata 10460maxresident)k
[trusty-testing] (timing) 0inputs+0outputs (0major+2608minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-checkbox-ng-unit
[trusty-testing] container-tests-checkbox-ng-unit: FAIL
[trusty-testing] stdout: https://paste.ubuntu.com/p/nTtQXVhyKf/
[trusty-testing] stderr: https://paste.ubuntu.com/p/qCWFs9ZGkP/
[trusty-testing] (timing) Command exited with non-zero status 1
[trusty-testing] (timing) 10.96user 0.87system 0:14.67elapsed 80%CPU (0avgtext+0avgdata 74044maxresident)k
[trusty-testing] (timing) 2224inputs+54184outputs (22major+478780minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-providers-internal
[trusty-testing] container-tests-providers-internal: PASS
[trusty-testing] (timing) 8.99user 0.77system 0:12.78elapsed 76%CPU (0avgtext+0avgdata 61428maxresident)k
[trusty-testing] (timing) 0inputs+48032outputs (0major+469107minor)pagefaults 0swaps
[trusty-testing] Fixing file permissions in source directory
[trusty-testing] Destroying container
Name: trusty-testing
State: STOPPED
[xenial] starting container
[xenial] (timing) 0.00user 0.01system 0:00.26elapsed 4%CPU (0avgtext+0avgdata 4932maxresident)k
[xenial] (timing) 0inputs+72outputs (0major+1434minor)pagefaults 0swaps
[xenial] provisioning container
[xenial] (timing) 31.10user 17.22system 5:32.36elapsed 14%CPU (0avgtext+0avgdata 82412maxresident)k
[xenial] (timing) 12288inputs+1504864outputs (68major+1439525minor)pagefaults 0swaps
[xenial-testing] Starting tests...
Found a test script: ./requirements/001-container-tests-plainbox-egg-info
[xenial-testing] 001-container-tests-plainbox-egg-info: PASS
[xenial-testing] (timing) 0.20user 0.03system 0:00.26elapsed 89%CPU (0avgtext+0avgdata 25356maxresident)k
[xenial-testing] (timing) 0inputs+88outputs (0major+9563minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-checkbox-documentation
[xenial-testing] container-tests-checkbox-documentation: PASS
[xenial-testing] (timing) 1.50user 0.08system 0:02.33elapsed 68%CPU (0avgtext+0avgdata 58768maxresident)k
[xenial-testing] (timing) 504inputs+9160outputs (1major+24750minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-checkbox-ng-unit
[xenial-testing] container-tests-checkbox-ng-unit: FAIL
[xenial-testing] stdout: https://paste.ubuntu.com/p/t2TFg7CcDD/
[xenial-testing] stderr: https://paste.ubuntu.com/p/P7v6W4xZPB/
[xenial-testing] (timing) Command exited with non-zero status 1
[xenial-testing] (timing) 11.64user 0.84system 0:15.35elapsed 81%CPU (0avgtext+0avgdata 72988maxresident)k
[xenial-testing] (timing) 3072inputs+54936outputs (26major+494802minor)pagefaults 0swaps
Found a test script: ./requirements/container-tests-providers-internal
[xenial-testing] container-tests-providers-internal: PASS
[xenial-testing] (timing) 9.63user 0.72system 0:12.60elapsed 82%CPU (0avgtext+0avgdata 63532maxresident)k
[xenial-testing] (timing) 0inputs+48392outputs (0major+484259minor)pagefaults 0swaps
[xenial-testing] Fixing file permissions in source directory
[xenial-testing] Destroying container
Name: xenial-testing
State: STOPPED