tests: Add better error message to debug test failure
tests: Add better error message to debug test failure

woutervanwijk/mopidy,priestd09/mopidy,woutervanwijk/mopidy,bencevans/mopidy,abarisain/mopidy,dbrgn/mopidy,adamcik/mopidy,jcass77/mopidy,ZenithDK/mopidy,mokieyue/mopidy,swak/mopidy,jcass77/mopidy,quartz55/mopidy,priestd09/mopidy,glogiotatidis/mopidy,glogiotatidis/mopidy,ali/mopidy,hkariti/mopidy,adamcik/mopidy,glogiotatidis/mopidy,ZenithDK/mopidy,tkem/mopidy,mokieyue/mopidy,glogiotatidis/mopidy,bacontext/mopidy,ZenithDK/mopidy,swak/mopidy,tkem/mopidy,quartz55/mopidy,hkariti/mopidy,quartz55/mopidy,jmarsik/mopidy,ali/mopidy,pacificIT/mopidy,bacontext/mopidy,mopidy/mopidy,abarisain/mopidy,liamw9534/mopidy,vrs01/mopidy,mopidy/mopidy,diandiankan/mopidy,kingosticks/mopidy,jmarsik/mopidy,jmarsik/mopidy,SuperStarPL/mopidy,rawdlite/mopidy,vrs01/mopidy,rawdlite/mopidy,bacontext/mopidy,hkariti/mopidy,diandiankan/mopidy,kingosticks/mopidy,ali/mopidy,dbrgn/mopidy,swak/mopidy,jcass77/mopidy,tkem/mopidy,bencevans/mopidy,ali/mopidy,SuperStarPL/mopidy,priestd09/mopidy,diandiankan/mopidy,jodal/mopidy,vrs01/mopidy,SuperStarPL/mopidy,dbrgn/mopidy,jmarsik/mopidy,quartz55/mopidy,bencevans/mopidy,SuperStarPL/mopidy,tkem/mopidy,liamw9534/mopidy,kingosticks/mopidy,hkariti/mopidy,vrs01/mopidy,jodal/mopidy,adamcik/mopidy,bencevans/mopidy,mokieyue/mopidy,rawdlite/mopidy,pacificIT/mopidy,pacificIT/mopidy,mokieyue/mopidy,dbrgn/mopidy,ZenithDK/mopidy,swak/mopidy,pacificIT/mopidy,jodal/mopidy,rawdlite/mopidy,mopidy/mopidy,bacontext/mopidy,diandiankan/mopidy