e2e: accept context from Ginkgo

Every ginkgo callback should return immediately when a timeout occurs or the
test run manually gets aborted with CTRL-C. To do that, they must take a ctx
parameter and pass it through to all code which might block.

This is a first automated step towards that: the additional parameter got added
with

    sed -i 's/\(framework.ConformanceIt\|ginkgo.It\)\(.*\)func() {$/\1\2func(ctx context.Context) {/' \
        $(git grep -l -e framework.ConformanceIt -e ginkgo.It )
    $GOPATH/bin/goimports -w $(git status | grep modified: | sed -e 's/.* //')

log_test.go was left unchanged.

test/e2e_node/runtimeclass_test.go

@@ -95,7 +95,7 @@ var _ = SIGDescribe("Kubelet PodOverhead handling [LinuxOnly]", func() {
 	f.NamespacePodSecurityEnforceLevel = admissionapi.LevelPrivileged
 	ginkgo.Describe("PodOverhead cgroup accounting", func() {
 		ginkgo.Context("On running pod with PodOverhead defined", func() {
-			ginkgo.It("Pod cgroup should be sum of overhead and resource limits", func() {
+			ginkgo.It("Pod cgroup should be sum of overhead and resource limits", func(ctx context.Context) {
 				if !framework.TestContext.KubeletConfig.CgroupsPerQOS {
 					return
 				}