Ensure python-openssl is not present

python-openssl should be installed from pip along with the rest of the
requirements. Not doing so leads to issues with versions of pyOpenSSL
that are too old.

Change-Id: I22a7d6e4080efbfcd1f86083505d015cf33ea885

manifests/init.pp

@@ -74,6 +74,12 @@ class nodepool (
 
   ensure_packages($packages, {'ensure' => 'present'})
 
+  $absent_packages = [
+    'python-openssl',
+  ]
+
+  ensure_packages($absent_packages, {'ensure' => 'absent'})
+
   if ! defined(Package['build-essential']) {
     package { 'build-essential':
       ensure => present,