Namespace-level Tekton Pruner ConfigMap updates do not trigger immediate pruning

Expected Behavior

Updating a namespace-level pruner ConfigMap should immediately reconcile and enforce the new pruning limits. The number of retained PipelineRuns should match the updated ConfigMap values without requiring additional PipelineRun events.

Actual Behavior

When a namespace-level pruner ConfigMap is updated, pruning does not occur immediately.
The new configuration is only applied after a PipelineRun completes (Succeeded or Failed) in the affected namespace.

Steps to Reproduce the Problem

1. Create a namespace-level pruner ConfigMap that overrides global pruning settings.
2. Create PipelineRuns in the namespace until pruning occurs (works as expected).
3. Update the namespace-level ConfigMap with new pruning values.
4. Observe that pruning does not occur after the update.
5. Trigger a new PipelineRun and wait for it to complete.
6. Observe that pruning now occurs using the updated configuration.

Additional Info

• Kubernetes version: 1.29.15

• Tekton Pipeline version: 1.6.0

• Tekton Pruner version: 0.3.4

Start by tracing how namespace-level pruner ConfigMap updates enter the controller and how reconciliation is triggered. Reproduce the issue by changing the ConfigMap without creating a PipelineRun, then verify that the retained PipelineRun count matches the updated limits immediately after the update.