Uploads.upload() polls forever with no timeout and leaks an open file handle

[aaronelliotross]

What's happening

Uploads.upload() (actionkit/uploads.py:19-34):

def upload(self, file_name, import_page):
    m = MultipartEncoderMonitor.from_fields(
        fields={
            'page': import_page,
            'upload': (file_name, open(file_name, 'rb'), 'text/csv'),
            'autocreate_user_fields': 'false',
        },
        callback=progressing,
    )

    upload_url = self.post(data=m, headers={'Content-Type': m.content_type})

    upload = self.poll(upload_url)
    while not upload['is_completed']:
        upload = self.poll(upload_url)
        time.sleep(1)

Two issues:

1. No timeout / max-attempt count on the polling loop. If ActionKit's import job never completes (or the is_completed field is never present/true for some reason), this hangs the calling process forever.
2. The file handle from open(file_name, 'rb') is never explicitly closed. It's only passed into MultipartEncoderMonitor.from_fields, which doesn't take ownership/close it after the request completes.

Suggested fix direction

• Add a max-attempt count or overall timeout to the polling loop, raising a clear exception (or returning a "still pending" result) if exceeded.
• Use a with open(file_name, 'rb') as fh: block (or otherwise ensure the handle is closed) around the request.

Test coverage

Pinned (not fixed) by tests/test_uploads.py::test_upload_polls_until_is_completed, which documents the unbounded-loop behavior explicitly in its docstring — it only terminates because the mocked poll() sequence is finite. Should be revisited once a timeout/max-attempts is added.