fix tornado failing test because of the availability of httpbin.org

[srikanthccv]

The tests make a call to httpbin.org, which may not be working all the time and tests fail. Mock and fix this.

[srikanthccv]

This is failing more often in more tests than just tornado instrumentation. Example run here https://github.com/open-telemetry/opentelemetry-python-contrib/actions/runs/4204426728/jobs/7295087981

[shalevr]

Urllib and Urllib3 instrumentation tests also use httpbin.org

[srikanthccv]

And they were failing as well randomly. It's random based on the availability status of the gttpbin

[shalevr]

Now the tests are failing for aiohttp-client because of the availability of httpbin.org.
I'm working to fix this issue and add mocks for requests