Previously the plugin exited with an error, if the target name could not
be resolved. Now this problem is handled just like an "unreachable"
situation.
Thanks, nitram2342!
Closes: #1091
By default, Net::Ping will report a good attempt even when the remote end returns "connection refused". By enabling service_check, the connection must have been established.
See https://perldoc.perl.org/Net/Ping.html#Functions