add unit test cases for annotations.cors
add unit test cases for annotations.cors

literalice/ingress,nevetS/ingress,coryfklein/ingress,chentao1596/ingress,kubernetes/ingress-nginx,canhnt/ingress,nicksardo/ingress,danielqsj/ingress,winfield-chen-hs/ingress,nicksardo/ingress,coryfklein/ingress,nicksardo/ingress,aledbf/ingress-nginx,jcmoraisjr/ingress,arjanschaaf/ingress,aledbf/ingress-nginx,literalice/ingress,matthewg/ingress,canhnt/ingress,kubernetes/ingress-nginx,matthewg/ingress,caicloud/ingress,porridge/ingress,caiyixiang/ingress,canhnt/ingress,canhnt/ingress,caiyixiang/ingress,danielqsj/ingress,aledbf/ingress-nginx,caicloud/ingress,jcmoraisjr/ingress,chentao1596/ingress,caicloud/ingress,kubernetes/ingress-nginx,jcmoraisjr/ingress,nicksardo/ingress,arjanschaaf/ingress,aledbf/ingress-nginx,kubernetes/ingress-nginx,porridge/ingress,kubernetes/ingress-gce,kubernetes/ingress-nginx,winfield-chen-hs/ingress,nevetS/ingress,caicloud/ingress,kubernetes/ingress-gce