Describe the bug
I started two long running requests, the first one takes 15 seconds and the second one takes 10 seconds. Then I go to the first request and press cancel, but nothing happens. Then I look at the second one, and see that it has been cancelled.

The cancel request button cancels the last started request, not the active request. I see the correct request duration as I switch

I expect

• to add some tests in https://github.com/ioggstream/openapi-resolver/blob/master/tests/test_cases.py
  for testing https://github.com/ioggstream/openapi-resolver/blob/master/openapi_resolver/__main__.py

Tests could just verify that main() works as expected.