defer close the link!

[serbrech]

Servicebus allows a maximum of 5000 open sessions.
Because we don't close it after each calls, the sessions stay active until they reach an idle timeout and get closed by the remote peer.
if you have enough load, you will reach max sessions pretty quickly as this is called for each message disposition, lock renewal, or management operations.

A better optimization would be to keep a dediccated management session around to avoid opening and closing so many sessions (handshake overhead)

[richardpark-msft]

Looks good, thank you for fixing that.

[serbrech]

erg, seems I changed some behavior.
got a nil pointer in my tests.

[serbrech]

I just reverted to defer in the for loop.
drawback is that it will wait to exit the func to close the links created within the for loop, instead of closing them as soon as it can. I think thats ok, even if it's not perfect. Eventually, the whole link management part for RPC calls need to be re-designed to be cached/reused