flake: templateinstance unexpectedly reported failure

[tnozicka]

https://openshift-gce-devel.appspot.com/build/origin-ci-test/pr-logs/pull/16061/test_pull_request_origin_extended_conformance_install_update/5182/

: [Conformance][templates] templateinstance readiness test should report ready soon after all annotated objects are ready 2m22s
/go/src/github.com/openshift/origin/test/extended/templates/templateinstance_readiness.go:145
Expected error:
    <*errors.errorString | 0xc42186d620>: {
        s: "templateinstance unexpectedly reported failure",
    }
    templateinstance unexpectedly reported failure
not to have occurred
/go/src/github.com/openshift/origin/test/extended/templates/templateinstance_readiness.go:144

Might be related to #15901 but the error differs.

[jim-minter]

Root cause is #13014.