PageBuilder - Unable to render LP edit on prod with varnish

blocks rendered by render ESI results with redirect to /login on every ESI fragment, which result with iframe redirect to login

Steps to reproduce:

1. install ee-demo 3.0   https://github.com/ezsystems/ezplatform-ee-demo/tree/3.0 and set the APP_ENV=prod
2. install varnish, you can use this substeps:
    2.1 download https://github.com/ezsystems/ezplatform-ee-demo/blob/3.0/.platform/varnish.vcl
    2.2 uncomment at line 8: 

vcl 4.1;
import std;

    2.3 replace at line 42:

set req.backend_hint = app.backend();

         with:

set req.backend_hint = ezplatform;

    2.4 add at line 25 and replace the ip with your host ip:

backend ezplatform {
    .host = "192.168.0.2";
    .port = "80";
}

    2.5 check your absolute path with pwd command and replace it in the command, run the command

docker run --name ez-varnish -v /abolute_path/to_your_dir/with_the_file/varnish.vcl:/etc/varnish/default.vcl -p 8080:80 -p 6082:6082 -d plopix/docker-varnish6

    2.6 verify that  maison.yourdomain.tld and maison.yourdomain.tld:8080 works, same with admin.yourdomain.tld and admin.yourdomain.tld:8080
3. run

docker exec -it ez-varnish /bin/bash

     inside the container run:

varnishadm "ban req.url ~ /"

4. remove the cache 

rm -rf var/cache/*

3. go to edit mode of LP  
     expected: you should see blocks nice and shiny, ready to be edited
     current: you will see redirect url in every LP block, and whole iframe redirect to login page after few seconds