AttributeError: 'str' object has no attribute 'formatted_name' error in integration testing

[berland]

This exception occurs in Komodo integration tests while running GUI tests:

Traceback (most recent call last):
  File "/tmp/f_scout_ci/actions-runner-07/_temp/test-kenv/root/lib64/python3.12/site-packages/ert/gui/simulation/experiment_panel.py", line 368, in run_experiment
    f"Queue system:\n{model.queue_config.queue_system.formatted_name}"
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'str' object has no attribute 'formatted_name'

Obviously related to d032a21

[berland]

Bug is also present in interactive sessions, so it is not caused by test-mocking.

[berland]

This bug seems related to this setting:

ert/src/ert/config/queue_config.py

Line 54 in 940b8be

use_enum_values=True,

[berland]

Residual issue is to reapply the reverted commit after merging of #12464

[berland]

Residual issue is to reapply the reverted commit after merging of #12464

Reapplied in #12559