fix(container): respect ConditionVirtualization service setting

* E.g. `opensuse-leap-151`:

```bash
kitchen@0e066e43d255:~> systemctl status ntpd
WARNING: terminal is not fully functional
-  (press RETURN)● ntpd.service - NTP Server Daemon
   Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled; vendor preset: disabled)
   Active: inactive (dead)
Condition: start condition failed at Sat 2019-10-26 04:11:32 UTC; 13min ago
           └─ ConditionVirtualization=!container was not met
     Docs: man:ntpd(1)
```

* Check for `Docker` for the time being (other containers _are_ possible) --
  replace earlier method of checking for the `kitchen` user:
  - `salt['environ.get']('SUDO_USER', '') == 'kitchen'`

ntp/ng/init.sls

@@ -26,8 +26,14 @@ ntpd_conf:
 {% endif %}
 
 {% if 'ntpd' in ntp.settings %}
+{%   set service_state = service.get(ntp.settings.ntpd) %}
+{#   Do not attempt to run the service in a container where the service is configured with #}
+{#   `ConditionVirtualization=!container` or similar (e.g. via. `kitchen-salt`) #}
+{%   if grains.os_family in ['Suse'] and salt['config.get']('virtual_subtype', '') in ['Docker'] %}
+{%     set service_state = 'dead' %}
+{%   endif %}
 ntpd:
-  service.{{ service.get(ntp.settings.ntpd) }}:
+  service.{{ service_state }}:
     - name: {{ ntp.lookup.service }}
     - enable: {{ ntp.settings.ntpd }}
     {%- if 'init_delay' in ntp.settings %}

test/integration/default/controls/services_spec.rb

@@ -8,13 +8,27 @@
     'ntpd'
   end
 
-control 'ntp service' do
+control 'ntp service (installed)' do
   impact 0.5
   title 'should be installed and enabled'
 
   describe service(service_name) do
     it { should be_installed }
     it { should be_enabled }
+  end
+end
+
+control 'ntp service (running)' do
+  impact 0.5
+  title 'should be running'
+  only_if(
+    'unable to run the service in a container due to its '\
+    '`ConditionVirtualization` setting'
+  ) do
+    platform[:family] != 'suse'
+  end
+
+  describe service(service_name) do
     it { should be_running }
   end
 end