Support new `local-network-access` permissions policy on iframes

Starting Chrome 142 a new permissions policy `local-network-access` is enabled by default which causes request to private network to fail.

References:

- https://wicg.github.io/local-network-access/
- https://developer.chrome.com/blog/local-network-access

I have a web extension that connects to a service that runs on our own private network, this was working without problems until Chrome 142
