chore(karma): use dots reporter by default
chore(karma): use dots reporter by default

dots is nicer for local testing, as you usually don't run a
ton of test suites, and the progress visualization is more important .
It's also more readable if you skip many tests (i.e. run isolated tests)

Closes #16167
angularbrasil/angular.js,dmuellner/angular.js,jbedard/angular.js,pbr1111/angular.js,arunkannan/angular.js,angularbrasil/angular.js,gkalpak/angular.js,eistrati/angular.js,marcin-wosinek/angular.js,angular/angular.js,angularbrasil/angular.js,ze-pequeno/angular.js,pbr1111/angular.js,reneploetz/angular.js,ze-pequeno/angular.js,Narretz/angular.js,gkalpak/angular.js,arunkannan/angular.js,angular/angular.js,angular/angular.js,eistrati/angular.js,reneploetz/angular.js,mosoft521/angular.js,mgol/angular.js,reneploetz/angular.js,dmuellner/angular.js,lgalfaso/angular.js,jbedard/angular.js,pbr1111/angular.js,angular/angular.js,angularbrasil/angular.js,eistrati/angular.js,Narretz/angular.js,ze-pequeno/angular.js,pbr1111/angular.js,dmuellner/angular.js,mosoft521/angular.js,dmuellner/angular.js,marcin-wosinek/angular.js,lgalfaso/angular.js,hnccho/angular.js,jbedard/angular.js,mgol/angular.js,reneploetz/angular.js,lgalfaso/angular.js,Narretz/angular.js,mosoft521/angular.js,hnccho/angular.js,marcin-wosinek/angular.js,ze-pequeno/angular.js,hnccho/angular.js,jbedard/angular.js,Narretz/angular.js,arunkannan/angular.js,lgalfaso/angular.js,gkalpak/angular.js,hnccho/angular.js,gkalpak/angular.js,mgol/angular.js,eistrati/angular.js,marcin-wosinek/angular.js,arunkannan/angular.js,mosoft521/angular.js,mgol/angular.js