nodes/htz.ex42-1048908: fix X-Forwarded-For header for matrix-media-repo

bundles/nginx/files/site_template

@@ -99,7 +99,7 @@ server {
 %    if ssl:
         proxy_set_header     X-Forwarded-Proto HTTPS;
 %    endif
-        proxy_set_header     X-Forwarded-Host ${domain};
+        proxy_set_header     X-Forwarded-Host ${options.get('x_forwarded_host', domain)};
 %    for option, value in options.get('proxy_set_header', {}).items():
         proxy_set_header     ${option} ${value};
 %    endfor

nodes/htz/ex42-1048908.py

@@ -358,6 +358,9 @@ nodes['htz.ex42-1048908'] = {
                         '/_matrix/media': {
                             'target': 'http://localhost:20090',
                             'client_max_body_size': '500M',
+                            # matrix-media-repo needs this to be the
+                            # homeserver address.
+                            'x_forwarded_host': 'franzi.business',
                         },
                         '/_synapse': {
                             'target': 'http://[::1]:20080',