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: I15200b393a0f8f8f0168c4504d9073ba5b8b4aea
Signed-off-by: Takashi Kajinami <kajinamit@oss.nttdata.com>

manifests/params.pp

@@ -5,6 +5,8 @@
 class mistral::params {
   include openstacklib::defaults
 
+  $pyver3 = $openstacklib::defaults::pyver3
+
   $client_package      = 'python3-mistralclient'
   $db_sync_command     = 'mistral-db-manage upgrade head'
   $db_populate_command = 'mistral-db-manage populate'
@@ -25,7 +27,7 @@ class mistral::params {
       $notifier_package_name      = 'openstack-mistral-notifier'
       $notifier_service_name      = 'openstack-mistral-notifier'
       $mistral_wsgi_script_path   = '/var/www/cgi-bin/mistral'
-      $mistral_wsgi_script_source = '/usr/bin/mistral-wsgi-api'
+      $mistral_wsgi_script_source = "/usr/lib/python${pyver3}/site-packages/mistral/api/wsgi.py"
     }
     'Debian': {
       $common_package_name        = 'mistral-common'

spec/classes/mistral_wsgi_apache_spec.rb

@@ -163,7 +163,7 @@ describe 'mistral::wsgi::apache' do
         when 'RedHat'
           {
             :wsgi_script_path   => '/var/www/cgi-bin/mistral',
-            :wsgi_script_source => '/usr/bin/mistral-wsgi-api'
+            :wsgi_script_source => '/usr/lib/python3.9/site-packages/mistral/api/wsgi.py',
           }
 
         end