Update packages and close session correctly when still on event loop

[lahariganti]

Swift package is failing to work well (swift package update) as version requirements of cross dependencies are not compatible.

https://github.com/Kitura/SwiftyRequest/compare/master...mbarnach:SwiftyRequest:master

[CLAassistant]

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2 out of 3 committers have signed the CLA.

:white_check_mark: mbarnach
:white_check_mark: lahariganti
:x: djones6
_{You have signed the CLA already but the status is still pending? Let us recheck it.}