Fixes: Invalid file_type breaks drag and drop (#7559)
* file type fix
* add changeset
* pdf test
* format
* test fixes
* file test fix
* file path fix
* new test
* format
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Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Hannah <hannahblair@users.noreply.github.com>
