Add Lambda Invoke permission without Internet access

In order to poll lambda function, crhelper tries to add permission for lambda to get invoked by event. When a lambda doesn't have access to internet, it keeps loading and gets failed after timeout.

Trace the crhelper polling path that adds Lambda invocation permission, then identify where the permission request waits for internet access. Check the relevant tests or add a focused reproduction for an internet-isolated Lambda; done means permission handling no longer hangs until timeout when the function has no internet access.

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