Issue with xblock-lti-consumer==2.7.4

[Arti3DPlayer]

Cannot unpack non-iterable Mock() object

Issue happens with this xblock https://github.com/edx/xblock-lti-consumer
version 2.7.4. For older version 1.2.1 everything works correctly.

Problem in this line:

https://github.com/edx/xblock-sdk/blob/744a4e2c35222f1c03cc5729e1bc5ea56e828376/workbench/runtime.py#L300

as it is expects UsageKey