snapd auto update packages even when connected to a metered Wi-Fi connection

[Eliastik]

When connecting to a Wi-Fi network shared connection from my phone, connected to a limited and metered mobile network, and even if I enabled the setting "Metered connection: has data limits and may incurs charge" in NetworkManager, snapd auto refreshes packages. It has consumed over 100 Mo of data to update chromium for example, and slowdown every other apps that connect to Internet.

Steps to reproduce:

- A snap package needs a refresh
- Connect to a Wi-Fi connection with the setting "Metered connection: has data limits and may incurs charge" enabled in NetworkManager

What was expected to happen:

- snapd should take into account the setting and don't update the package automatically in this case

What happened:

- The snapd package will auto refresh

My environment:

- Ubuntu 22.04.3 LTS
- NetworkManager 1.36.6
- snapd 2.58+22.04.1