test: fix ping test, ping can fail after having one response and that is ok (aka we really need a new http-api)

Author: daviddias

js/src/ping/ping.js

@@ -66,7 +66,6 @@ module.exports = (createCommon, options) => {
       const count = 2
       ipfsA.ping(invalidPeerId, { count }, (err, responses) => {
         expect(err).to.exist()
-        expect(responses).to.not.exist()
         done()
       })
     })