MINIFICPP-2487 - Destroy PyException while holding GIL

[adamdebreceni]

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[szaszm]

why?

[adamdebreceni]

why?

PyException holds a reference to the python exception object, when it escapes the scope of GIL (into an outer catch block) its destruction crashes the application and the python library logs the reason as not holding the lock, this can occur when e.g. the describe function is malformed (declared with the incorrect number of positional arguments)