Remove unused GnuPG keyring

This was added by commit de7975c--Gerrit change 7--so old it
predates Change-Id headers in the repo (and, apparently, commit
messages). Today it seems to be completely unused. The pubring.gpg
contained just this one key:

    pub   2048R/32EE128C 2010-08-15
    uid                  OpenStack Hudson <hudson@openstack.org>
    sub   2048R/92E212FC 2010-08-15

Based on discussion in IRC, Monty vaguely recalls this might have
been related to DEB package building once upon a time (something we
no longer do and wouldn't configure from this module anyway when
eventually want to start doing again).

Change-Id: I70c3b82185681ee64791cda653360c26a93bd466

manifests/jenkinsuser.pp

@@ -109,23 +109,6 @@ class jenkins::jenkinsuser(
     source  => 'puppet:///modules/jenkins/ssh_config',
   }
 
-  file { '/home/jenkins/.gnupg':
-    ensure  => directory,
-    owner   => 'jenkins',
-    group   => 'jenkins',
-    mode    => '0700',
-    require => File['/home/jenkins'],
-  }
-
-  file { '/home/jenkins/.gnupg/pubring.gpg':
-    ensure  => present,
-    owner   => 'jenkins',
-    group   => 'jenkins',
-    mode    => '0600',
-    require => File['/home/jenkins/.gnupg'],
-    source  => 'puppet:///modules/jenkins/pubring.gpg',
-  }
-
   file { '/home/jenkins/.config':
     ensure  => directory,
     owner   => 'jenkins',

spec/acceptance/slave_spec.rb

@@ -65,7 +65,6 @@ describe 'puppet-jenkins slave module', :if => ['debian', 'ubuntu'].include?(os[
     jenkins_user_files = [
       file('/home/jenkins/.bash_logout'),
       file('/home/jenkins/.bashrc'),
-      file('/home/jenkins/.gnupg/pubring.gpg'),
       file('/home/jenkins/.profile'),
       file('/home/jenkins/.ssh/authorized_keys'),
     ]