weblate/test_merge_canonical_changes: Fix the last failing test. (sysadmin#17745)

hefeerequested to merge
hefee/puppet-tails:hefee/fix_last_test into master

I still do not understand what is going on, why we logger is not catched by unittests. AS the test in it self successfully end if called as only test:

python3 -m nose --tests tests.test_merge_canonical_changes:TestMCCMain.test_nothing_to_do

In the end one test influence others. This patch gives us at least a working workaround.

Merge request reports