Align Orign and Host header (#14970)

* Align Orign and Host header

* Before this change the Host: header was runserver. Seems to be set by
  nginx upstream flow.
* After this change we explicitly set the Host: header
* More about CSRF checks ...
  CSRF checks that Origin == Host. Think about how the browser works.

  <browser goes to awx.com>
  "I'm executing javascript that I downloaded from awx.com (ORIGIN) and
  I'm making an XHR POST request to awx.com (HOST)"
  Server verifies; Host: header == Origin: header; OK!

  vs. the malicious case.

  <hacker injects javascript code into google.com>
  <browser goes to google.com>
  "I'm executing javascript that I downloaded from google.com (ORIGIN)
  and I'm making an XHR POST request to awx.com (HOST)"
  Server verifies; Host: header != Origin: header; NOT OK!

* Update awx/settings/development.py

---------

Co-authored-by: Hao Liu <44379968+TheRealHaoLiu@users.noreply.github.com>

tools/docker-compose/ansible/roles/sources/templates/nginx.locations.conf.j2

@@ -46,4 +46,5 @@ location @fallback {
     # Add trailing / if missing
     rewrite ^(.*)$http_host(.*[^/])$ $1$http_host$2/ permanent;
     proxy_pass http://runserver;
+    proxy_set_header Host $http_host;
 }