Add error in certificate check #869

Job	Run time
build / Build (windows)	6m 52s
build / Build	6m 24s
Integration Tests (etcdrestore)	3m 41s
Integration Tests (kubeflags)	8m 27s
Integration Tests (etcdsnapshot)	9m 26s
Integration Tests (longhorn)	4m 41s
Integration Tests (flannelnone)	2m 55s
Integration Tests (cacertrotation)	3m 14s
Integration Tests (startup)	8m 46s
Integration Tests (custometcdargs)	2m 15s
Integration Tests (localstorage)	3m 5s
Integration Tests (secretsencryption)	3m 49s
Integration Tests (certrotation)	3m 24s
	1h 6m 59s

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