Trivial: Fix the pep8 warning

The yaml should start with "---"

Change-Id: Ica4e1888cc5e7c0f552044ff06c6719694e039c8

examples/playbook.yml

@@ -1,3 +1,4 @@
+---
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at

extras/ansible-role-requirements.yml

@@ -1,3 +1,4 @@
+---
 - name: ansible-zookeeper
   scm: git
   src: https://github.com/Chillisystems/ansible-zookeeper

extras/conf.d/monasca.yml

@@ -1,3 +1,4 @@
+---
 # The infra nodes that will be running the monasca services
 monasca-infra_hosts:
   aio1:

extras/os_horizon/defaults/main.yml

@@ -1,3 +1,4 @@
+---
 horizon_enable_monasca_ui: True
 horizon_grafana_url: "https://{{ external_lb_vip_address }}:3000"
 horizon_pip_packages:

extras/os_horizon/tasks/horizon_post_install.yml

@@ -1,3 +1,4 @@
+---
 - name: Enable the monasca-ui-dashboard Horizon panel
   file:
     src: "{{ horizon_lib_dir }}/monitoring/enabled/_50_admin_add_monitoring_panel.py"

extras/user_secrets.yml

@@ -1,3 +1,4 @@
+---
 grafana_admin_password:
 grafana_galera_password:
 monasca_container_mysql_password:

tests/ansible-role-requirements.yml

@@ -1,3 +1,4 @@
+---
 - name: apt_package_pinning
   src: https://git.openstack.org/openstack/openstack-ansible-apt_package_pinning
   scm: git

zuul.d/project.yaml

@@ -1,3 +1,4 @@
+---
 # Copyright 2017, Rackspace US, Inc.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");