PinotDriver File Handle Leaks

[brandonwardell20]

The PinotDriver.connect() method leaks the PinotClientTransport and PinotControllerTransport when an exception is thrown trying to construct the PinotConnection. This highly impacts applications that utilize other drivers, and eventually causes the server which has registered the driver to crash.

Suggested solution:

1. Convert PinotClientTransport and PinotControllerTransport to temporary variables, and close them individually, and safely, when exceptions are thrown getting the connection. Like so:

try
{
            if (pinotClientTransport != null) {
                pinotClientTransport.close();
            }
        } catch (PinotClientException ignored) {
        }

        try {
            if (pinotControllerTransport != null) {
                pinotControllerTransport.close();
            }
        } catch (PinotClientException ignored) {
        }

3. Add a URL check to return null if the URL is not expected, avoiding allocating resources altogether if not necessary.
   Like so: if (!this.acceptsURL(url)) { return null; }

[Jackie-Jiang]

Fixed by #12356