Fix interpolation - '' -> ""

manifests/init.pp

@@ -179,7 +179,7 @@ class freeradius (
   }
   concat::fragment { 'proxy_header':
     target  => "${freeradius::fr_basepath}/proxy.conf",
-    content => '# Proxy config\n',
+    content => "# Proxy config\n",
     order   => '05',
   }
 
@@ -436,7 +436,7 @@ class freeradius (
     "${freeradius::fr_basepath}/clients.conf",
     "${freeradius::fr_basepath}/sql.conf",
   ]:
-    content => '# FILE INTENTIONALLY BLANK\n',
+    content => "# FILE INTENTIONALLY BLANK\n",
     mode    => '0644',
     owner   => 'root',
     group   => $freeradius::fr_group,

spec/classes/freeradius_spec.rb

@@ -121,7 +121,7 @@ describe 'freeradius' do
       it do
         is_expected.to contain_concat__fragment('proxy_header')
           .with(
-            'content' => '# Proxy config\n',
+            'content' => "# Proxy config\n",
             'order'   => '05',
             'target'  => '/etc/raddb/proxy.conf'
           )
@@ -364,7 +364,7 @@ describe 'freeradius' do
         ].each do |file|
           is_expected.to contain_file(file)
             .with(
-              'content' => '# FILE INTENTIONALLY BLANK\n',
+              'content' => "# FILE INTENTIONALLY BLANK\n",
               'group'   => 'radiusd',
               'mode'    => '0644',
               'notify'  => 'Service[radiusd]',