tests: clean journalctl logs on trusty

[sergiocazzolato]

This is a way to reduce the size of the journalctl logs on ubuntu 14.04.
This is needed to improve the quality of the tests bacause some of them are using journalctl to check that the actions are done.
I also will help to make more readable the logs when a test fail.

[zyga]

Last time I checked there was no journald on 14.04, has that changed since?

[sergiocazzolato]

Well, I tested that manually in a vm and then in linode with ubuntu 14.04 and it is working, I ran the suite and I was monitoring the logs and it was cleaned for every test.

[codecov-io]

Codecov Report

Merging #3432 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3432      +/-   ##
==========================================
- Coverage   77.56%   77.55%   -0.01%     
==========================================
  Files         371      371              
  Lines       25519    25519              
==========================================
- Hits        19793    19792       -1     
- Misses       3976     3977       +1     
  Partials     1750     1750

Impacted Files	Coverage Δ
interfaces/sorting.go	90% <0%> (-3.34%)	⬇️

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[mvo5]

Looks good, thanks for this!

[fgimenez]

Thanks!