feat(api): Refinement around handling of mixed text file / non-text file requests #106

[kravetsmic]

Summary

Added validation for text files in test API. If the user sends text files to the file endpoint, or files to the text file endpoint, he will get exception from server with message Type {file_content_type} not supported for files / text files endpoint. and status code 400.

Added additional tests.

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Closes issue #106

[cragwolfe]

This isn't actually addressing the ordering issue in #106 .

As a change on its own, I also think this change is too restrictive, and the API is better of being less opiniated. E.g., a file sent with the files parameter could be any mimetype, inclluding text/plain.

on the other hand, in the text_files case, there are quite a few more valid plain text mimetypes floating around out there (e.g. html, xml, ...). so, i think for now it is better not to try to enumerate them.