proxy_set_header X-Forwarded-Proto $schema; needed for HTTPS

Running-changedetection.io-behind-a-reverse-proxy-sub-directory.md

@@ -5,6 +5,7 @@ Without this, the application will not listen to the following variables
 ```
  proxy_set_header Host "localhost";
  proxy_set_header X-Forwarded-Prefix /app;
+ proxy_set_header X-Forwarded-Proto $schema;
 ```
 
 Easiest example is to create an extra docker-compose YML file and run it with the shipped version
@@ -52,6 +53,7 @@ server {
         proxy_pass http://changedetection-app:5000/;
         proxy_set_header Host "localhost";
         proxy_set_header X-Forwarded-Prefix /app;
+        proxy_set_header X-Forwarded-Proto $schema;
     }
 }
 ```