Several fixes to improve the stability of E2E testing (#4056)

1. Support to customize the restic restore helper image
2. Use a seperated context when doing the clean up works
3. Wait a while before doing the the restore for aws to avoid #1799

Signed-off-by: Wenkai Yin(尹文开) <yinw@vmware.com>

pkg/install/install.go

@@ -50,6 +50,7 @@ var kindToResource = map[string]string{
 	"Deployment":               "deployments",
 	"DaemonSet":                "daemonsets",
 	"Secret":                   "secrets",
+	"ConfigMap":                "configmaps",
 	"BackupStorageLocation":    "backupstoragelocations",
 	"VolumeSnapshotLocation":   "volumesnapshotlocations",
 }