Log if theres a misconfigured code

[dsubak]

Description (What does it do?)

Adds a log message for the misconfiguration encountered here

Essentially, the code existed, but it was not linked up such that Discount.b2b_contracts() returned an empty list. In this codepath, that's not really expected, so it dropped through after performing no attachment and returned a 200. This doesn't change any of the behavior around the fallback, but it does provide visibility into what's happening for us.

Screenshots (if appropriate):

Code in question on production:

How can this be tested?

• Add a contract in the admin page. I used the following minimal settings.

- Visit `http://mitxonline.odl.local:9080/api/v0/b2b/attach/test/` and hit POST. - You should get back an empty list and in the web container's UI, we should see an error like the following:

Additional Context

• There's an open question as to whether or not we should expose the error to the user. I'm happy to add that if we feel that it's useful.

[github-actions]

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