* Fix using wrong array index in log to avoid potential panic
* Increase gRPC connection timeout and add the timeout resolv.conf option
This makes sure the dns client is able to failover to a second
configured nameserver, if present. That is the case then when using the
dns `file` manager and a resolv.conf file generated for netbird.
* On file backup restore, remove the first NS if it's the netbird NS
* Bump dns mangager discovery message from debug to info to ease debugging
In the case of disabled stub listeren the list of name servers is unordered. The solution is to configure the resolv.conf file directly instead of dbus API.
Because third-party services also can manipulate the DNS settings the agent watch the resolv.conf file and keep it up to date.
- apply file type DNS manager if in the name server list does not exist the 127.0.0.53 address
- watching the resolv.conf file with inotify service and overwrite all the time if the configuration has changed and it invalid
- fix resolv.conf generation algorithm
