Add signal handler for catching Ctrl-C on kubetest
Add signal handler for catching Ctrl-C on kubetest

When operating e2e test, hack/e2e.go process creates kubetest process,
and it creates hack/ginkgo-e2e.sh process. hack/ginkgo-e2e.sh process
is created as a process group and it is necessary to kill it as the
process group when receiving Ctrl-C(SIGINT).
This PR adds the signal handler on kubetest to kill hack/ginkgo-e2e.sh
process.

solve #43051

kargakis/test-infra,shyamjvs/test-infra,fejta/test-infra,fejta/test-infra,cblecker/test-infra,dims/test-infra,monopole/test-infra,cjwagner/test-infra,BenTheElder/test-infra,krousey/test-infra,brahmaroutu/test-infra,shyamjvs/test-infra,kubernetes/test-infra,lavalamp/test-infra,jlowdermilk/test-infra,michelle192837/test-infra,rmmh/kubernetes-test-infra,kargakis/test-infra,shashidharatd/test-infra,spxtr/test-infra,ixdy/kubernetes-test-infra,jessfraz/test-infra,kubernetes/test-infra,krzyzacy/test-infra,shyamjvs/test-infra,BenTheElder/test-infra,kargakis/test-infra,abgworrall/test-infra,krzyzacy/test-infra,lavalamp/test-infra,brahmaroutu/test-infra,foxish/test-infra,michelle192837/test-infra,foxish/test-infra,krousey/test-infra,jessfraz/test-infra,dims/test-infra,lavalamp/test-infra,michelle192837/test-infra,cjwagner/test-infra,brahmaroutu/test-infra,pwittrock/test-infra,monopole/test-infra,BenTheElder/test-infra,abgworrall/test-infra,piosz/test-infra,spxtr/test-infra,shyamjvs/test-infra,mindprince/test-infra,ixdy/kubernetes-test-infra,krzyzacy/test-infra,cjwagner/test-infra,jlowdermilk/test-infra,cjwagner/test-infra,kubernetes/test-infra,piosz/test-infra,kubernetes/test-infra,piosz/test-infra,kubernetes/test-infra,kargakis/test-infra,BenTheElder/test-infra,jlowdermilk/test-infra,rmmh/kubernetes-test-infra,cjwagner/test-infra,mindprince/test-infra,BenTheElder/test-infra,pwittrock/test-infra,mindprince/test-infra,fejta/test-infra,krzyzacy/test-infra,pwittrock/test-infra,kargakis/test-infra,fejta/test-infra,shyamjvs/test-infra,lavalamp/test-infra,cblecker/test-infra,spxtr/test-infra,cblecker/test-infra,monopole/test-infra,kubernetes/test-infra,lavalamp/test-infra,cblecker/test-infra,dims/test-infra,ixdy/kubernetes-test-infra,krousey/test-infra,rmmh/kubernetes-test-infra,lavalamp/test-infra,spxtr/test-infra,shyamjvs/test-infra,jlowdermilk/test-infra,krzyzacy/test-infra,fejta/test-infra,abgworrall/test-infra,jlowdermilk/test-infra,michelle192837/test-infra,monopole/test-infra,ixdy/kubernetes-test-infra,foxish/test-infra,BenTheElder/test-infra,cblecker/test-infra,jessfraz/test-infra,mindprince/test-infra,shashidharatd/test-infra,dims/test-infra,dims/test-infra,shashidharatd/test-infra,jessfraz/test-infra,spxtr/test-infra,abgworrall/test-infra,dims/test-infra,piosz/test-infra,ixdy/kubernetes-test-infra,pwittrock/test-infra,shashidharatd/test-infra,brahmaroutu/test-infra,monopole/test-infra,jlowdermilk/test-infra,rmmh/kubernetes-test-infra,piosz/test-infra,cblecker/test-infra,abgworrall/test-infra,krousey/test-infra,jessfraz/test-infra,foxish/test-infra,krzyzacy/test-infra,krousey/test-infra,fejta/test-infra,foxish/test-infra,monopole/test-infra,rmmh/kubernetes-test-infra,brahmaroutu/test-infra,michelle192837/test-infra,brahmaroutu/test-infra,shashidharatd/test-infra,pwittrock/test-infra,jessfraz/test-infra,kargakis/test-infra,michelle192837/test-infra,cjwagner/test-infra,mindprince/test-infra