Remove unnecessary mapping that could cause issues

docker/frontend/nginx.conf

@@ -6,11 +6,6 @@ http {
     include /etc/nginx/mime.types;
     default_type application/octet-stream;
 
-    # Add .mjs MIME type mapping
-    types {
-        text/javascript mjs;
-    }
-
     # Gzip compression
     gzip on;
     gzip_vary on;