Fix index.html caching

[aeldar]

There is a non-desirable behavior, in case of updated environment variables the outdated version of index.html is served, as it uses cached version with the help of service worker.
Currently to get an up-to-date version of index.html forced reloading with CTRL+F5 should be used.
Should be fixed to serve actual version of index.html without forced reloading.