Mark finish_reason and other properties as required

[rattrayalex]

Attempts to resolve openai/openai-node#82

Note I am very uncertain whether these changes are correct; they are just guesses. Please audit them before merging.

[rattrayalex]

Noting a few things I was particularly unsure of.

[rattrayalex]

Note that I assume that index would always be present, but delta and finish_reason may not be here; I have not checked whether that tends to be the case.

[athyuttamre]

delta and finish_reason are also always present, we can make this required.

[rattrayalex]

Ah, then presumably finish_reason should be marked as nullable?

[rattrayalex]

And is delta nullable, or would it be '' on the last chunk when it's just a finish reason?

[athyuttamre]

finish_reason is nullable, whereas delta is always a dictionary with every key (and sub key) optional.

[rattrayalex]

I am not sure if the logprobs key would always be present; it is marked as nullable.

[athyuttamre]

This is a bug — the v1/edits response doesn't support logprobs as a parameter or a response field. Can we remove from both request and response?

[rattrayalex]

Noting a few things I was particularly unsure of.

[athyuttamre]

Couple of fixes, thanks for doing this!

[rattrayalex]

Thanks Atty! Back to you – want to make sure we get the typing around delta right.

[athyuttamre]

Clarified about delta / finish_reason