Deleted according to flaky test process:
https://2u-internal.atlassian.net/wiki/spaces/TE/pages/12812492/Flaky+Test+Process
Flaky test ticket: https://2u-internal.atlassian.net/browse/CR-6899
Failed multiple times with this error, but not consistently:
```
FAILED lms/djangoapps/commerce/tests/__init__.py::DeprecatedRestApiClientTest::test_tracking_context - requests.exceptions.ConnectionError: HTTPSConnectionPool(host='ecommerce.example.com', port=443): Max retries exceeded with url: /api/v2/baskets/1/ (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f0708b91f50>: Failed to establish a new connection: [Errno -2] Name or service not known'))
```
Note that there is another test class with a name differing by only one
letter earlier in this file, `DeprecatedRestApiClientTests` (plural), with
a method with the same name. That one hasn't been failing.
9146ab29f7