[redirects-web] Land missing ProxyPreserveHost

[Andrea Veri <averi src gnome org>]

commit 9ca135fc3b9dff8dd7b9acefa7804395d1aca89c
Author: Andrea Veri <averi redhat com>
Date:   Wed Feb 19 14:48:27 2020 +0100

    Land missing ProxyPreserveHost

 app_data/httpd-cfg/gtk.org.conf | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/app_data/httpd-cfg/gtk.org.conf b/app_data/httpd-cfg/gtk.org.conf
index 12e07f3..b779f39 100644
--- a/app_data/httpd-cfg/gtk.org.conf
+++ b/app_data/httpd-cfg/gtk.org.conf
@@ -9,6 +9,7 @@
     ProxyPass /.well-known/acme-challenge !
     ProxyPassReverse / https://infrastructure.pages.gitlab.gnome.org/gtk-web/ 
     ProxyAddHeaders Off
+    ProxyPreserveHost Off
 
     <LocationMatch "^/.well-known/acme-challenge">
       RedirectMatch ^(.*) https://letsencrypt.gnome.org$1