The unit tests of bob.bio.spear are failing in bob.nightlies

The extra-builds in bob.nightlies are failing. The details on the error are given below.

Probably, this is related to the changes made in bob.bio.base, here: bob.bio.base!80 (merged)

Thank you for your help!

@mguenther if you think the bug is not related to changes in bob.bio.base, please, re-assign the issue. Thanks!

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ERROR: bob.bio.spear.test.test_databases.test_timit
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Traceback (most recent call last):
  File "/home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/lib/python2.7/site-packages/nose/case.py", line 197, in runTest
    self.test(*self.arg)
  File "/home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/lib/python2.7/site-packages/bob/bio/spear/test/test_databases.py", line 102, in test_timit
    check_database(database, groups=('dev',))
  File "/home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/lib/python2.7/site-packages/bob/bio/base/test/test_database_implementations.py", line 27, in check_database
    assert len(database.all_files()) > 0
  File "/home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/lib/python2.7/site-packages/bob/bio/base/database/filelist/query.py", line 209, in all_files
    raise ValueError("ZT score files are requested, but no such files are defined in group %s for protocol %s", group, self.protocol)
ValueError: ('ZT score files are requested, but no such files are defined in group %s for protocol %s', 'dev', '2')

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Ran 13 tests in 63.195s

FAILED (errors=1)
(06:39:18.319) Error: Command Failed "/home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/bin/coverage run --source=bob.bio.spear /home/gitlab-runner/builds/0d638152/0/bob/bob.nightlies/build-prefix/bin/nosetests -sv bob.bio.spear"
(06:39:18.321) Error: Command Failed "./_ci/test.sh"
ERROR: Job failed: exit status 1