test(rubocop): fix all violations

test/integration/default/controls/config_spec.rb

@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 control 'SyslogNG configuration' do
   title 'should match desired lines'
 
   str =
-    '''
+    '
 source s_src {
   internal();
 };
@@ -20,7 +22,7 @@ log {
   filter(f_syslog3);
   destination(d_syslog);
 };
-'''
+'
 
   describe file('/etc/syslog-ng/syslog-ng.conf') do
     it { should exist }

test/integration/default/controls/package_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 control 'SyslogNG package' do
   title 'should be installed'
 

test/integration/default/controls/service_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 syslogng_service =
   case platform[:name]
   when 'arch'
@@ -12,5 +14,4 @@ control 'SyslogNG service' do
     it { should be_enabled }
     it { should be_running }
   end
-
 end