Code review comment for plainbox-provider-resource:release

The merge was fine but running tests failed.

[trusty] starting container
[trusty] Unable to start ephemeral container!
[trusty] stdout:
[trusty] stderr: https://paste.ubuntu.com/26545886/
[trusty] NOTE: unable to execute tests, marked as failed
[trusty] Destroying failed container to reclaim resources
Destroyed container trusty-testing
[xenial] starting container
[xenial] (timing) 0.00user 0.00system 0:00.16elapsed 4%CPU (0avgtext+0avgdata 4892maxresident)k
[xenial] (timing) 376inputs+72outputs (1major+1424minor)pagefaults 0swaps
[xenial] provisioning container
[xenial] (timing) 50.82user 9.06system 2:02.75elapsed 48%CPU (0avgtext+0avgdata 107780maxresident)k
[xenial] (timing) 718568inputs+2323976outputs (490major+1975725minor)pagefaults 0swaps
[xenial-testing] Starting tests...
Found a test script: ./requirements/container-tests-provider-resource-generic
[xenial-testing] container-tests-provider-resource-generic: PASS
[xenial-testing] (timing) 20.56user 1.44system 0:37.81elapsed 58%CPU (0avgtext+0avgdata 64148maxresident)k
[xenial-testing] (timing) 7976inputs+98296outputs (63major+479209minor)pagefaults 0swaps
[xenial-testing] Fixing file permissions in source directory
[xenial-testing] Destroying container
Name: xenial-testing
State: STOPPED