If its failing because of a system error, Then probably ignorable.
If its failing due to test breaking. It might be worth looking into.
Do daniel's point,
If you just feel like ignoring it, ignore it.
In this case however, the error seems to be an issue between master talking to agent, so not likely your code.
14:35:58 [Pipeline] }
14:35:58 Terminated
14:37:45 win2012-e11d91 was marked offline: Connection was broken: java.util.concurrent.TimeoutException: Ping started at 1563399225815 hasn't completed by 1563399465816
14:37:45 at hudson.remoting.PingThread.ping(PingThread.java:134)
14:37:45 at hudson.remoting.PingThread.run(PingThread.java:90)