Fix printing revision info twice

Properly applying mozilla/mozregression@f1adf45ae5d98245548d87e139e1c91e6a6d59ad, see https://bugzilla.mozilla.org/show_bug.cgi?id=1042173#c12
Merge pull request #117 from hurda/master

Fix printing revision info twice
mozdevice 0.23
mozregression 0.23 for reals ;)