don't hardcode keystone-package tag to memcached package

Do not hardcode keystone-package tag to memcached package because
resource can already be in catalog with another tag. Keep standard
'openstack' tag.

Change-Id: Iee5f8015cbf40ca0e9a435a7de919ebdb74cf93f

manifests/init.pp

@@ -434,7 +434,7 @@ class horizon(
   if $cache_backend =~ /MemcachedCache/ {
     ensure_packages('python-memcache',
       { name   => $::horizon::params::memcache_package,
-        tag    => ['openstack', 'horizon-package']})
+        tag    => ['openstack']})
   }
 
   package { 'horizon':

spec/classes/horizon_init_spec.rb

@@ -216,7 +216,7 @@ describe 'horizon' do
       it {
         is_expected.to contain_package('python-memcache').with(
           :ensure => 'present',
-          :tag    => ['openstack', 'horizon-package']
+          :tag    => ['openstack']
          )
       }
     end