Yamllint fixes (#4410)

* Lint everything in the repository with yamllint

* yamllint fixes: syntax fixes only

* yamllint fixes: move comments to play names

* yamllint fixes: indent comments in .gitlab-ci.yml file

inventory/sample/group_vars/all/all.yml

@@ -1,3 +1,4 @@
+---
 ## Directory where etcd data stored
 etcd_data_dir: /var/lib/etcd
 
@@ -9,17 +10,17 @@ bin_dir: /usr/local/bin
 ## this node for example.  The access_ip is really useful AWS and Google
 ## environments where the nodes are accessed remotely by the "public" ip,
 ## but don't know about that address themselves.
-#access_ip: 1.1.1.1
+# access_ip: 1.1.1.1
 
 
 ## External LB example config
 ## apiserver_loadbalancer_domain_name: "elb.some.domain"
-#loadbalancer_apiserver:
-#  address: 1.2.3.4
-#  port: 1234
+# loadbalancer_apiserver:
+#   address: 1.2.3.4
+#   port: 1234
 
 ## Internal loadbalancers for apiservers
-#loadbalancer_apiserver_localhost: true
+# loadbalancer_apiserver_localhost: true
 
 ## Local loadbalancer should use this port
 ## And must be set port 6443
@@ -32,12 +33,12 @@ nginx_kube_apiserver_healthcheck_port: 8081
 ## for mounting persistent volumes into containers.  These may not be loaded by preinstall kubernetes
 ## processes.  For example, ceph and rbd backed volumes.  Set to true to allow kubelet to load kernel
 ## modules.
-#kubelet_load_modules: false
+# kubelet_load_modules: false
 
 ## Upstream dns servers used by dnsmasq
-#upstream_dns_servers:
-#  - 8.8.8.8
-#  - 8.8.4.4
+# upstream_dns_servers:
+#   - 8.8.8.8
+#   - 8.8.4.4
 
 ## There are some changes specific to the cloud providers
 ## for instance we need to encapsulate packets with some network plugins
@@ -46,43 +47,43 @@ nginx_kube_apiserver_healthcheck_port: 8081
 ## like you would do when using openstack-client before starting the playbook.
 ## Note: The 'external' cloud provider is not supported.
 ## TODO(riverzhang): https://kubernetes.io/docs/tasks/administer-cluster/running-cloud-controller/#running-cloud-controller-manager
-#cloud_provider:
+# cloud_provider:
 
 ## Set these proxy values in order to update package manager and docker daemon to use proxies
-#http_proxy: ""
-#https_proxy: ""
+# http_proxy: ""
+# https_proxy: ""
 
 ## Refer to roles/kubespray-defaults/defaults/main.yml before modifying no_proxy
-#no_proxy: ""
+# no_proxy: ""
 
 ## Some problems may occur when downloading files over https proxy due to ansible bug
 ## https://github.com/ansible/ansible/issues/32750. Set this variable to False to disable
 ## SSL validation of get_url module. Note that kubespray will still be performing checksum validation.
-#download_validate_certs: False
+# download_validate_certs: False
 
 ## If you need exclude all cluster nodes from proxy and other resources, add other resources here.
-#additional_no_proxy: ""
+# additional_no_proxy: ""
 
 ## Certificate Management
 ## This setting determines whether certs are generated via scripts.
 ## Chose 'none' if you provide your own certificates.
 ## Option is  "script", "none"
 ## note: vault is removed
-#cert_management: script
+# cert_management: script
 
 ## Set to true to allow pre-checks to fail and continue deployment
-#ignore_assert_errors: false
+# ignore_assert_errors: false
 
 ## The read-only port for the Kubelet to serve on with no authentication/authorization. Uncomment to enable.
-#kube_read_only_port: 10255
+# kube_read_only_port: 10255
 
 ## Set true to download and cache container
-#download_container: true
+# download_container: true
 
 ## Deploy container engine
 # Set false if you want to deploy container engine manually.
-#deploy_container_engine: true
+# deploy_container_engine: true
 
 ## Set Pypi repo and cert accordingly
-#pyrepo_index: https://pypi.example.com/simple
-#pyrepo_cert: /etc/ssl/certs/ca-certificates.crt
+# pyrepo_index: https://pypi.example.com/simple
+# pyrepo_cert: /etc/ssl/certs/ca-certificates.crt