quoting the output from the $PIPE

playbooks/hosts/jenkins.cloud.fedoraproject.org.yml

@@ -23,7 +23,7 @@
   tasks:
   - include: $tasks/cloud_setup_basic.yml
   - name: add root keys for other allowed users
-    action: authorized_key user=root key=$PIPE(${auth_keys_from_fas} ${root_auth_users})
+    action: authorized_key user=root key='$PIPE(${auth_keys_from_fas} ${root_auth_users})'
   
   handlers:
   - include: $handlers/restart_services.yml