Fix build on macOS, update binaryninja-api.

[turbocool3r]

Fixes build on macOS and also updates binaryninja-api to the latest stable version.

On macOS using ProcessPoolExecutor for some reason caused behdict to be empty. This changes ProcessPoolExecutor to ThreadPoolExecutor. Using it doesn't make much sense since there is GIL, but at least it works fine.

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[droptopx]

I believe behdict is empty as a result of ProcessPoolExecutor using spawn by default (where all resources aren't inherited by the child processes) on macOS instead of fork. Passing an mp_context=mp.get_context("fork") to the ProcessPoolExecutor fixes this issue but this is considered unsafe on macOS as it can cause crashes. Seems to work without crashes for this use case though.

[cfircohen]

Sorry for the (very) late response. I can't test on a macOS, but happy to accept a PR that fixes this issue.