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/lock_contention_linux_test.go

@@ -20,6 +20,7 @@ limitations under the License.
 package e2enode
 
 import (
+	"context"
 	"time"
 
 	"golang.org/x/sys/unix"
@@ -38,7 +39,7 @@ const contentionLockFile = "/var/run/kubelet.lock"
 var _ = SIGDescribe("Lock contention [Slow] [Disruptive] [NodeSpecialFeature:LockContention]", func() {
 
 	// Requires `--lock-file` & `--exit-on-lock-contention` flags to be set on the Kubelet.
-	ginkgo.It("Kubelet should stop when the test acquires the lock on lock file and restart once the lock is released", func() {
+	ginkgo.It("Kubelet should stop when the test acquires the lock on lock file and restart once the lock is released", func(ctx context.Context) {
 
 		ginkgo.By("perform kubelet health check to check if kubelet is healthy and running.")
 		// Precautionary check that kubelet is healthy before running the test.