Network Drive ftest fails if ping() is called too many times

[seanstory]

Bug Description

When we tried to use ping() inside the backend loop for connectors, the Network Drive ftest began failing. The current theory is that this is because ping() creates a connection, and that too many calls to it exhausts the connection pool. We need to fix this so that we can work onhttps://github.com//issues/2173

To Reproduce

1. revert Revert "Add logic to send a ping to connector's backend every loop (#2105)" #2148
2. Run the network drive ftest

Expected behavior

We should be able to ping the source as much as we want, without it compromising the stability of the connector