Add CentOS 7 for integration check and gate jobs

I'd really like to re-enable integration tests for CentOS since we use
it quite a bit. This should also hopefully catch any issues that might
be missed.

Change-Id: I2be43a81c5c8d4e36253b740affe7223f7a54acd
Signed-off-by: Lance Albertson <lance@osuosl.org>

.zuul.yaml

@@ -8,8 +8,9 @@
     timeout: 1800
 
 - job:
-    name: openstack-chef-integration
+    name: openstack-chef-integration-ubuntu
     parent: base
+    nodeset: ubuntu-bionic
     description: Run integration tests with openstack-chef on Ubuntu Bionic
     required-projects: openstack/openstack-chef
     pre-run: playbooks/pre-integration.yaml
@@ -17,16 +18,29 @@
     post-run: playbooks/post.yaml
     timeout: 5400
 
+- job:
+    name: openstack-chef-integration-centos
+    parent: base
+    nodeset: centos-7
+    description: Run integration tests with openstack-chef on CentOS 7
+    required-projects: openstack/openstack-chef
+    pre-run: playbooks/pre-integration.yaml
+    run: playbooks/integration.yaml
+    post-run: playbooks/post.yaml
+    timeout: 5400
+
 - project-template:
     name: openstack-chef-jobs
     check:
       jobs:
         - openstack-chef-delivery
-        - openstack-chef-integration
+        - openstack-chef-integration-ubuntu
+        - openstack-chef-integration-centos
     gate:
       jobs:
         - openstack-chef-delivery
-        - openstack-chef-integration
+        - openstack-chef-integration-ubuntu
+        - openstack-chef-integration-centos
 
 - project:
     templates:

Rakefile

@@ -127,7 +127,7 @@ end
 
 def _save_logs(prefix, log_dir)
   sh %(sleep 25)
-  %w(nova neutron keystone glance apache2 rabbitmq mysql mysql-default openvswitch mariadb).each do |project|
+  %w(nova neutron keystone glance httpd apache2 rabbitmq mysql mysql-default openvswitch mariadb).each do |project|
     sh %(mkdir -p #{log_dir}/#{prefix}/#{project})
     sh %(sudo cp -rL /etc/#{project} #{log_dir}/#{prefix}/#{project}/etc || true)
     sh %(sudo cp -rL /var/log/#{project} #{log_dir}/#{prefix}/#{project}/log || true)

environments/integration.json

@@ -11,11 +11,6 @@
       "install": {
         "version": "10.1"
       }
-    },
-    "yum": {
-      "epel": {
-        "enabled": false
-      }
     }
   },
   "override_attributes": {