1. Expected Behavior
   When a statefulset in a TektonInstallerSet is removed, it should remove pod and statefulset that we configured in tektoninstallerset.

1. Actual Behavior
   When a statefulset in a TektonInstallerSet is removed, it remains there.

1. Steps to Reproduce the Problem

1. Use any feature that utilizes statefulset like https://github.com/tektoncd/operator/pull/2361  or Results without external DB in OpenShift.
2. Later on change from statefulset to deployment or internal to external DB, statefulset will remain.

Upstream Issue:

https://github.com/tektoncd/operator/issues/2372

Acceptance criteria: 

Definition of Done:

Build Details:

Additional info (Such as Logs, Screenshots, etc):

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