Replace wsgi script

pbr is removing support for wsgi_script due to changes in setuptools.
Use the wsgi script module python code instead.

Note that this change only touches CentOS code. Ubuntu and Debian will
be updated later when we bump the release used in our testing.

Change-Id: I99e8632d5ca92b873bcc5c9243d34e791ef877c2
Signed-off-by: Takashi Kajinami <kajinamit@oss.nttdata.com>

manifests/params.pp

@@ -5,6 +5,8 @@
 class designate::params {
   include openstacklib::defaults
 
+  $pyver3 = $openstacklib::defaults::pyver3
+
   $state_path                = '/var/lib/designate'
   $log_dir                   = '/var/log/designate'
   $client_package_name       = 'python3-designateclient'
@@ -28,7 +30,7 @@ class designate::params {
       $producer_package_name        = 'openstack-designate-producer'
       $worker_package_name          = 'openstack-designate-worker'
       $designate_wsgi_script_path   = '/var/www/cgi-bin/designate'
-      $designate_wsgi_script_source = '/usr/bin/designate-api-wsgi'
+      $designate_wsgi_script_source = "/usr/lib/python${pyver3}/site-packages/designate/wsgi/api.py"
     }
     'Debian': {
       # package name

spec/classes/designate_wsgi_apache_spec.rb

@@ -161,7 +161,7 @@ describe 'designate::wsgi::apache' do
         when 'RedHat'
           {
             :wsgi_script_path   => '/var/www/cgi-bin/designate',
-            :wsgi_script_source => '/usr/bin/designate-api-wsgi'
+            :wsgi_script_source => '/usr/lib/python3.9/site-packages/designate/wsgi/api.py',
           }
 
         end