Don't crash serverless process on error in async invocations

[janicduplessis]

Description

Currently when invoking a function asynchronously and throwing an error to report failure it causes the whole serverless offline server to crash.

Motivation and Context

I think it makes more sense to just log the error in this case and keep the server running.

How Has This Been Tested?

Tested locally that throwing an error in a function invoked asynchronously no longer causes the sls offline process to crash.

Screenshots (if appropriate):

N/A

[dherault]

This PR has conflicts, sorry for the long delay. I will close it in a few days if it does not get rebased.

[dnalborczyk]

thank you for the PR @janicduplessis it seems this change removing re-throwing the error has already been incorporated into the code base. unfortunately not sure when this has occurred.

if you think the problem still exists feel free to (re-)create a PR. closing this in the meanwhile.