ClusterRoles '*aggregate*' should be deleted when RolloutManager is deleted

[jgwest]

ClusterRoles argo-rollouts-aggregate-to-admin, argo-rollouts-aggregate-to-edit and argo-rollouts-aggregate-to-view do not get deleted upon deletion of Rolloutmanager instance.

To reproduce

• Install the operator
• Create a RolloutManager instance
• Delete the instance and check if the relevant clusterroles are deleted 

Actual Results

ClusterRoles argo-rollouts-aggregate-to-admin, argo-rollouts-aggregate-to-edit and argo-rollouts-aggregate-to-view do not get deleted

Expected results:

ClusterRoles argo-rollouts-aggregate-to-admin, argo-rollouts-aggregate-to-edit and argo-rollouts-aggregate-to-view should get deleted

Fix Criteria

• The above cluster roles/bindings should be deleted, similar to how we are already deleting the other CR/CRB that we create (See this PR https://github.com/argoproj-labs/argo-rollouts-manager/pull/69)
• E2E/unit test to verify the expected behaviour

[jgwest]

Red Hat External JIRA tracker: https://issues.redhat.com/browse/GITOPS-5388