Merge pull request #91961 from openshift-cherrypick-robot/cherry-pick-91792-to-pipelines-docs-1.19

[pipelines-docs-1.19] RHDEVDOCS 6420 Pruner config: annotations should be under metadata

Author: mburke5678

modules/op-annotations-for-automatic-pruning-taskruns-pipelineruns.adoc

@@ -34,7 +34,7 @@ For example, the following annotations retain all task runs and pipeline runs cr
 kind: Namespace
 apiVersion: v1
 # ...
-spec:
+metadata:
   annotations:
     operator.tekton.dev/prune.resources: "taskrun, pipelinerun"
     operator.tekton.dev/prune.keep-since: 7200