AdGuard misbehaves when it's set as always-on and it receives a connectivity change event

[ameshkov]

Steps to reproduce

1. Install the latest AdGuard nightly (2.12.1)
2. Ensure that pref.vpn.disable.reconfigure is unchecked
3. Set AG as an "always-on" VPN
4. Trigger connectivity change (disable or enable wi-fi for instance)

Expected behavior

AG is restarted successfully.

Actual behavior

VPN fails to start.

[ameshkov]

Resolved in adguard-android/pull-requests/397

[TPS]

Now #3327