tox: Run tests with 4 processes in parallel
tox: Run tests with 4 processes in parallel

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