e2e: skip AllNodesReady when the test skipped framework initialization

This addresses a problem caused by
https://github.com/kubernetes/kubernetes/pull/112043: because the AfterEach
which invokes AllNodesReady always runs, including tests that skipped early,
those tests ran into a nil pointer access. This increased the size of log
files. The tests still worked.

test/e2e/framework/node/init/init.go

@@ -30,6 +30,12 @@ func init() {
 	framework.NewFrameworkExtensions = append(framework.NewFrameworkExtensions,
 		func(f *framework.Framework) {
 			ginkgo.AfterEach(func() {
+				if f.ClientSet == nil {
+					// Test didn't reach f.BeforeEach, most
+					// likely because the test got
+					// skipped. Nothing to check...
+					return
+				}
 				e2enode.AllNodesReady(f.ClientSet, 3*time.Minute)
 			})
 		},