Adjust Konflux PR CEL to release-2.15

Signed-off-by: Dale Haiducek <[email protected]>

Author: dhaiducek

.tekton/config-policy-controller-acm-215-pull-request.yaml

@@ -8,7 +8,7 @@ metadata:
     build.appstudio.redhat.com/target_branch: '{{target_branch}}'
     pipelinesascode.tekton.dev/cancel-in-progress: "true"
     pipelinesascode.tekton.dev/max-keep-runs: "3"
-    pipelinesascode.tekton.dev/on-cel-expression: event == "pull_request" && target_branch == "main"
+    pipelinesascode.tekton.dev/on-cel-expression: event == "pull_request" && target_branch == "release-2.15"
   creationTimestamp:
   labels:
     appstudio.openshift.io/application: release-acm-215