Add nop-image resource to pipline trigger template

Add nop-image resource to pipelinerun as the referred pipeline has a new
`builtNopImage` param (tektoncd/pipeline#3041)

Signed-off-by: Nikhil Thomas <nikthoma@redhat.com>

Author: nikhil-thomas

tekton/resources/nightly-release/overlays/pipeline/template.yaml

@@ -28,6 +28,9 @@
       - name: builtEntrypointImage
         resourceRef:
           name: entrypoint-image
+      - name: builtNopImage
+          resourceRef:
+            name: nop-image
       - name: builtKubeconfigWriterImage
         resourceRef:
           name: kubeconfigwriter-image