Ignore risks from e2e testing

This is to follow up a recent finding [1].

Further digging shows that the related risks to our e2e tests are `TestAlertFeatureE2ETestOTA1813`, `SyntheticRiskA`.

This pull ignores the risks with prefix `TestAlertFeatureE2ETest` similar to [2].

I will fix `SyntheticRiskA` by modifying "fauxinnati" so that the risks coming from it have the prefix too.

This will recover the health of the TP-enabled jobs in CI.

[1]. #1367 (comment)

[2]. openshift/origin#30929

Author: hongkailiu

install/0000_90_cluster-version-operator_02_prometheusrule_servicemonitor.yaml

@@ -20,7 +20,7 @@ spec:
         description: The conditional update risk {{ "{{ $labels.risk }}" }} might apply to the cluster because of {{ "{{ $labels.reason }}" }}, and the cluster update to a version exposed to the risk is not recommended. For more information refer to 'oc adm upgrade'.
         runbook_url: https://github.com/openshift/runbooks/blob/master/alerts/cluster-version-operator/OpenShiftUpdateRiskMightApply.md
       expr: |
-        max by (namespace, risk, reason) (last_over_time(cluster_version_risk_conditions{job="cluster-version-operator", condition="Applies"}[5m]) != 0)
+        max by (namespace, risk, reason) (last_over_time(cluster_version_risk_conditions{job="cluster-version-operator", condition="Applies", risk!~"TestAlertFeatureE2ETest.*"}[5m]) != 0)
       for: 10m
       labels:
         severity: warning