fix typo in state and reference export methods

[christianrauch]

Description

The controller_manager may report something like

Controller '%s' is chainable, but does not export any state or reference interfaces. Did you override the on_export_method() correctly?

But the method on_export_method() does not exist. Since it tests for export_state_interfaces() and export_reference_interfaces(), I assume this is supposed to be on_export_state_interfaces_list() and on_export_reference_interfaces_list().

Is this user-facing behavior change?

Yes. It changes the reported string.

Did you use Generative AI?

No.

Additional Information

TODOs

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