ipv4: check that pre-1.43 route behavior is restored
In 1.43.3 we did a change to always re-add routes that NM thinks should be there, even if they are removed externally:
This breaks user setups and is being reverted.
https://bugzilla.redhat.com/show_bug.cgi?id=2218866
NetworkManager branch:
Edited by Beniamino Galvani