Use stable Chrome in Circle
Use stable Chrome in Circle

Related https://github.com/sinonjs/sinon/issues/1969

Perhaps this will fix the intermittent failures that we're seeing on
Circle

fatso83/Sinon.JS,fatso83/Sinon.JS,cjohansen/Sinon.JS,fatso83/Sinon.JS,mroderick/Sinon.JS,cjohansen/Sinon.JS,mroderick/Sinon.JS,cjohansen/Sinon.JS,mroderick/Sinon.JS