put the apros upstream def back

The lms role gets installed first.  by referencing this upstream server,
we introduce a dependency on the upstream definition before it is
defined by the apros role.

playbooks/roles/nginx/templates/edx/app/nginx/sites-available/lms.j2

@@ -10,6 +10,12 @@ upstream lms-backend {
     {% endfor %}
 
 }
+ 
+upstream apros_app_server {
+    {% for host in nginx_apros_gunicorn_hosts %}
+      server {{host}}:{{mcka_apros_gunicorn_port}} fail_timeout=0;
+    {% endfor %}
+}
 
 {%- if EDXAPP_ENABLE_RATE_LIMITING -%}
 # Make Zone