[fix] strip auth params from multipart/form-data post request

[bdtky]

Fixes an api error for multipart/form-data when passing the openai api key as a param (#27).

I have tested this works with Files.create_file/3 using a pdf document. I haven't touched the tests since I didn't see a precedent for when the api key is passed as a param. Open to feedback / happy to make additional changes, or to coauthor the PR, as is convenient.

[dvcrn]

Thanks for this! Let me go ahead and merge this to get it into the next release. Could you try adding a test in a separate PR? I think this is something we should add testcases for

[dvcrn]

Released in https://github.com/dvcrn/ex_openai/releases/tag/1.6.0

[bdtky]

Thanks for this! Let me go ahead and merge this to get it into the next release. Could you try adding a test in a separate PR? I think this is something we should add testcases for

Yes I'd be happy to! I should have time tomorrow or early next week, so I will send another PR soon.

I am thinking to add a small sample pdf in the testdata, create a new cassette and assert the request body when calling with api key in opts. Please let me know if you prefer another approach!