upgrade.go: wait some time after node upgrade

For the "Cluster should remain functional during upgrade" test, TRT
noticed flakes from the step that verifies that deamonsets are running
on all expected nodes afer an upgrade.  This flake was caused by the
verification of the deamonset happening too quickly after the upgrade.
As soon as the last upgraded node becomes ready the check happens, but it
doesn't always leave enough time for the deamonset to restart, thus
causing the test to fail.

Signed-off-by: Damien Grisonnet <[email protected]>

Author: dgrisonnet

test/e2e/upgrade/upgrade.go

@@ -188,6 +188,9 @@ var _ = g.Describe("[sig-arch][Feature:ClusterUpgrade]", func() {
 						clusterUpgrade(f, client, dynamicClient, config, upgCtx.Versions[i]),
 						fmt.Sprintf("during upgrade to %s", upgCtx.Versions[i].NodeImage))
 				}
+				// Sleep to give some time to the workloads on the last upgraded
+				// node to restart.
+				time.Sleep(30 * time.Second)
 			},
 		)
 	})