Switch ensure style for packages

manifests/hostmaster.pp

@@ -52,7 +52,7 @@ class aegir::hostmaster (
     ensure_packages(
       concat(['nginx'], $php),
       {
-        'ensure' => 'present',
+        'ensure' => present,
         'before' => Package['aegir'],
       }
     )
@@ -63,7 +63,7 @@ class aegir::hostmaster (
   # Note: this may fail for some versions of Aegir:
   # @see https://www.drupal.org/project/provision/issues/2979947
   package { 'aegir':
-    ensure       => 'installed',
+    ensure       => present,
     name         => $package_name,
     responsefile => '/etc/dpkg/aegir.response',
     require      => File['/var/lib/dpkg/aegir.response'],