Async NodeJS lambda handlers should have a maximum of two parameters, not three.

Currently, we recognize exported NodeJS functions with three or fewer parameters as potential lamdba handlers. For asynchronous functions, we should lower this limit to two.

Locate the logic that recognizes exported NodeJS functions as Lambda handlers and any existing coverage for asynchronous handlers. Reproduce the current three-parameter behavior, then verify that asynchronous handlers accept at most two parameters while the existing synchronous behavior remains unchanged.

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